Question 12. What results do you obtain? After removing the electrodes from the solution, we find that copper metal gets deposited on the plate at the negative of the battery. Answer: Question 1. Sun is the main source of heat energy. Why the iron cans are electroplated with tin ? Activity 1 (NCERT Textbook, Page 173) Static electricity. (c) cathode Which one of the following is a weak electrolyte ? [NCERT] For example: All metals including metal wires, copper wires, aluminium foil, etc. Can you explain the reason ? Uses of Electroplating. Understanding the power of electricity we humans harness is necessary for the wise use and creation of this valuable resource. Electric current can produce magnetic effect also. But when salt is dissolved in distilled water and again tested, the bulb glows which shows that water containing salts conduct electricity. Question 3. Objects that are electroplated are door handles, taps, rims of cycles, showers, the handlebar of cycles and bikes, gas burner, tin cans, metallic almirahs, buckles of belts, etc. Is it safe for the electrician to carry out electrical repairs outdoors during heavy downpour? Recall the definition of a chemical change that you learnt in Class VII. Question 10. Paheli had heard that rainwater is as good as distilled water. What could be the reasons ? (a) magnetic energy into chemical energy (iv) The liquid may be an insulator, i.e., a poor conductor of electricity. Zinc coatings prevent the corrosion of steel articles. Good conductors are those conductors that allow current to pass through them. [NCERT]. The salts separate out and deposit on the sides of the container. Dissolve two teaspoonfuls of copper sulphate in it. Which is the most common application of chemical effect of current ? (b), Question 3. The 21 all-electric BYD heavy duty trucks used by Anheuser-Busch in California since 2019 is still the largest Class 8 truck deployment in North America. Question 8. Answer: After the electroplating of a spoon with silver, it was found that the anode has become thin. Why? 14.1. Why are LEDs more useful for testing the flow of electric current ? Which electrode should be attached to the positive terminal of the battery and why? Question 6. Question 8. Explain the process of electroplating of copper. Answer: Explain. Question 9. Answer: If not, what can we do to make it conducting ? Match. Join the free ends of the tester together fora moment. (b), Question 8. Question 6. Activity 3 (NCERT Textbook, Page 174) Question 2. Wrap copper wires around the metal caps of the carbon rods and join them to a battery (Fig. Why electric fires are extinguished with either using CO 2 extinguisher or mud but not water? Does the bulb of the tester glow? The writing appears on the paper. This completes the circuit of the tester and the bulb should glow. There are specific disposal guidelines for environmental protection. If the tester is working, it can be used to test the materials, i.e., whether it is a conductor or non-conductor of electricity. The bulb in the tester does not glow when current is passed through it. Firemen shuts off the main electrical supply for the area because water is a good conductor of electricity and the firemen can get electrocuted. (iii) both liquids are equally conducting. So, the deflection of the compass needle is more. The compass needle will show deflection with tap water, lemon juice and sodium chloride solution. In case of a fire, before the firemen use the water hoses, they shut off the main electrical supply for the area. If they are, then replace the bulb with another bulb. Question 4. No, pure water doesn’t conduct electricity. If the current in the circuit is small, how can we test its presence ? LEDs require very little energy and glow even if a small current is passing through the circuit. Answer: Gravity. The sea water contains more salts dissolved in it as compared to the tap water. A thin plate of pure copper and a thick rod of impure copper are used as electrodes. This is the Volvo VRN Electric, the company's first electric class-8 truck. Is it safe for the electrician to carry out electrical repairs outdoors during heavy downpour? Chemical effects of electric current are used in the working of _____ (a) Electrolytic cells (b) Galvanic cells (c) Electrochemical cells (d) None of these. Answer: The passage of an electric current through a solution causes ……………….. effects. Why should you not touch electrical appliances with wet hands ? Name the process of depositing a layer, of any desired metal on another material by means of electricity. Question 2. A tester is used to check the conduction of electricity through two liquids, labelled A and B. In each case observe whether the magnetic needle shows deflection or not. So, the fire¬men shut off the electric supply before spraying water to save themselves and other people from electrocution. Place a small compass needle inside it. Answer: Attach the free ends of the wires to a LED. the movement of electrons. Water is dissociated into its constituent gases, i.e., hydrogen and oxygen. Dinesh is wants to study the chemical effect of current at home. Answer: Chemical Effects of Electric Current Class 8 Extra Questions Higher Order Thinking Skills. Does pure water conduct electricity? Answer: A change in the electric potential change equals the change in electric potential energy per unit charge. In what proportion the two products from electrolysis of water are obtained ? A tester is used to check the conduction of electricity through two liquids, labelled A and B. The iodide ions (I- ) react with starch to turn blue black. Answer: Flow of Electrons in the Matter. Wrap an electric wire a few times around the tray. In this activity the bulb glows which shows that lemon juice and vinegar both conducts electricity, hence they are good conductors of electricity. Can we call the change taking place in the solution a chemical change? Take care that the ends are not more than 1 cm apart but at the same time do not touch each other. When the free ends of a tester are dipped into a solution, the magnetic needle shows deflection. Answer: How would you classify lemon juice or vinegar—a good conductor or a poor conductor? What could be the reasons? (b) Alcohol Does lemon juice or vinegar conduct electricity? Electroplating. (c) Dilute sulphuric acid Other uses include paint sprayers, air filters and dust removal. A tester can be made by attaching one free end of the wire to a terminal of a battery and another wire from other terminal of the battery to a bulb. Electric Current: The flow of electrons in any material is termed as an electric current. Pour about two teaspoonfuls of distilled water in each of them. What is CFL ? Oxygen bubbles are formed on the electrode connected to the positive terminal of the battery and hydrogen bubbles are formed on the other electrode. Explain how it can be used for writing. What is the objective of electroplating ? Open up your curtains and let the sun shine in! In 2014, nearly half of electricity used by U.S. manufacturers was for operating machinery.3 1. What is LED? How can the magnetic effect be used as a tester ? The filament of the bulb is heated due to current and then it glows. Why we cannot make the whole article with chromium ? Graphite. Coal is generally used in thermal power generation which further helps to produce electricity. What are conductors ? The sum of electric potential differences along any closed loop in a DC circuit is zero. Do you notice any gas bubbles near the electrodes? Question 20. [NCT 2011] What is the disadvantage of electroplating done in the factories ? Question 5. Thus food, stored in iron cans, is prevented from being spoilt due to iron by electroplating it by tin. If the tester is put in distilled water, the bulb of the tester does not glow. Explain your answer. These charges can be at rest or moving .Learn how these moving charges constitute current electricity. Give the construction of LED. (ii) The bulb may be fused. Repeat the activity with other liquids such as tap water, vegetable oil, milk, honey. 14.5. may cause the magnetic needle to deflect. Compact Fluorescent Lamps. Answer: What is the Voltage (V) of the rice cooker? Good/Poor Conducting Liquids. Electric eels use electricity to ward off enemies. The free copper gets deposited on the plate acting as cathode. Question 7. Jaya sets up a circuit as given below. Answer: Answer: Hydroxyl ions (OH )move towards the anode and oxygen is collected on it. (a) anode When electric current is passed through copper sulphate solution, the copper sulphate breaks up into copper and sulphate ions. Question 7. It is found that the bulb of the tester glows brightly for liquid A while it glows very dimly for liquid B. [NCERT] Chemical Effects of Electric Current Class 8 Science NCERT Intext Activities Solved. We can test the presence of the small current by using a LED instead of the bulb. Answer: Why ? (d) semi-insulator Question 4. Why ? Question 7. Answer: In metals electric current is conducted by flow of electrons. Thus, lemon juice, vinegar, tap water, milk, curd and water, and soda are good conductors of electricity while vegetable oil, honey, kerosene oil, and distilled water are poor conductors of electricity or insulators. The deflection in magnetic needle shows that the circuit is complete and the solution conducts electricity, i.e., it is a good conductor. Answer: Gradually, a layer of copper builds up on the plate. Distilled water does not have any salts dissolved in it, but rain water may have some impurities in it. Can we do electroplating on it to protect is from corrosion ? Answer: Question 6. They can produce a shock of around 500 volts. Answer: LED glows showing the flow of current. Rainwater is pure water which is an insulator but it gets mixed with air pollutants like sulphur dioxide and nitrogen oxides and form acidic solution, which is a good conductor of electricity. We cannot make the whole article from it because it is a very costly metal. Electric eels use electricity to ward off enemies. Answer: What is the difference between current flowing through metals and current flowing through liquids ? [NCT 2011] Now dissolve a pinch of common salt in distilled water. (d) electroplating. Bridges and automobiles are prevented from rusting by plating them with zinc. Test. Answer: Question 9. Explain why they do this. Answer: Distilled water is a This is static electricity. Two famous scientists, Thomas Edison and Nikola Tesla, once had an argument over what kind of electricity we should use in our homes, AC or DC. Question 3. (c) semi-conductor Chemical Effects of Electric Current - Class 8 : Notes. resistance 240 = 240 V R= 8 Current (I) = 30 =8A V R= I 39. Question 10. It is found that the bulb of the tester glows brightly for liquid A while it glows very dimly for liquid B. Classify the following liquids into conductors and insulators : lemon juice, , distilled water, tap water, milk. Solution: Activity 7 (NCERT Textbook, Page 177) To her surprise, she found that the compass needle showed deflection. If the electric potential is negative in the direction of electric current and the Most liquids that conduct electricity are solutions of …………, ………. Dip the ends of the wire in the given liquid. This process is known as chemical effects of current. Answer: (d) Nitric acid The lightning conductor used in building protects the building by : The bulb does not glow even though the circuit is complete because the current is too small. Our bodies use electricity to communicate including telling our heart to keep beating. (c) If you pass current through copper sulphate solution, copper gets deposited on the plate connected to the ________ terminal of the battery. Good Conductors of Electricity: The materials which allow the current to pass through them are known as good conductors. Changes of colour of solutions may occur depending on what solution and electrodes are used. (d) sides of the container Add a little sugar to the distilled water in the third cap and dissolve it. It is concluded that when electric current is passed through the copper sulphate solution, copper sulphate dissociates into copper and sulphate. Activity 6 (NCERT Textbook, Page 176) Explain your answer. Spell. (iii) The cells may be used up. Conducting properties of liquid cannot be compared in this manner. Answer: So, the compass needle showed deflection. Now remove the electrodes from the solution and look at them carefully. Current electricity is when an electrical charge is given a path to move through. Question 14. may be the current is so weak that it does not heat the filament of the bulb allowing it to glow. Kirchhoff’s Second Law is a consequence of the conservation of energy. Answer: Heat energy: It is the energy due to the motion of molecule. (b) chemical 14.2). Explain why they do this. Solution: A metal is released in the electrolysis of a salt. Decoration of articles by giving them a layer for e.g., silver plating on cutlery. Does pure water conduct electricity ? Chromium has a good shine, it resists scratches and is corrosion resistant. The liquid is a conductor and the circuit is also complete, but the bulb does not glow. Answer: Answer: Question 5. Which of the following metal is not extracted by electrolysis? (b), Question 6. However, if the bulb does not glow, it means that the tester is not working. 8. 25% of the city of San Francisco's energy is generated by wind power. Answer: Or, your cells are used up? Question 11. In this activity, if the bulb does not glow, it means that either the connections of the circuit are loose or the bulb is fused or cells are used up. Take another piece of wire and connect it to the other terminal of the battery (Fig. Yes, the solution does conduct electricity. You may also get distilled water from a medical store or a doctor or a nurse). Answer: Answer: Electrical energy: The energy produced due to the flow of charge is called electrical energy .it is used widely in electric appliances. (b), Question 5. Answer: This completes the circuit of the tester and the bulb should glow. Answer: A household uses the following electric appliances: (i) Refrigerator of rating 400 W for ten hours each day. PLAY. Solved Examples for You. No, it is not advisable for electrician to carry out electrical repairs during heavy downpour because water is a good conductor of electricity and the person can get shock. How are bridges and automobiles prevented from rusting ? Question 3. Question 19. Question 4. What do you conclude this time? Therefore, we can be electrocuted in case we touch appliances with wet hands. LED is Light Emitting Diode. Electrolysis is the breaking up of a compound from its solution on passing electric current through the electrolyte. Answer: Materials which do not allow electric current to flow through them are called insulators. Electricity Uses. During electroplating, the silver metal from the anode is deposited on the cathode. Take a filter paper soaked in potassium iodide solution to which a pinch of starch is added. Place them in fresh lemon fruit. Answer: But the bulb does not glow. (b) Oxalic acid Answer: 3.00. b) An electric iron of resistance 20Ωtakes a current of … Take out carbon rods carefully from two discarded cells. We prefer not to do electroplating on iron used for bridges because it is very costly. Now connect one free end of the wire to the terminal of a battery. (b) cathode The decomposition of an electrolyte when electricity is passed through it, is called Name one non-metal which a good conductor of electricity. Or, the bulb is fused? Air is an insulator of electricity. Your tester with two free ends of the wire is ready. Chromium is used for electroplating because it has a shiny appearance, does not corrode and is scratch resistant. Electricity is a part of our daily life. Question 13. Have you ever imagined how electricity is produced and what's the science behind it? Nickel and chromium-coated articles are used in automobiles and household appliances. (d) electro refining Today, the modern sources of entertainment starting from listening music from MP3 players,watching Television, playing movies in DVDs or VCDs or VCRs runs on electricity. Every molecule possesses kinetic energy and the sum of K.E is heat energy. Can you ex¬plain the reason? Is air an insulator or conductor of electricity ? Humans cannot survive without it. Answer: Why is chromium used for electroplating ? (b) electrical energy into chemical energy (7) Electric iron, mixer and grinder, microwave oven, electric geyser, electric kettle, washing machine, radio set, television set, stereo system computer all work because there is electricity. The bulb does not glow because distilled water is an insulator, since it does not have dissolved salts. Answer: Question 17. Vinegar, lemon juice and tap water. Activity 4 (NCERT Textbook, Page 175) The entire NCERT textbook questions have been solved by best teachers for you. Question 13. Answer: Explain why these deposits occur. Answer: As water is a good conductor of electricity so it can cause electrocution. How can you make a tester for testing whether a given material is a conductor or an insulator ? Question 6. The possible reasons for this are : Question 4. Grade 8 Science - Electricity. Free PDF Download - Best collection of CBSE topper Notes, Important Questions, Sample papers and NCERT Solutions for CBSE Class 8 Science Chemical Effects of Electrical Current. We will need copper sulphate and two copper plates of size around 10 cm x 4 cm. (d) Vinegar The bulb does not glow in the set-up shown in figure. Examples are copper, aluminium, etc. Find PowerPoint Presentations and Slides using the power of XPowerPoint.com, find free presentations research about Electricity And Magnetism Class 8 PPT We call these two rods electrodes. Add a teaspoonful of salt or a few drops of lemon juice to water to make it more conducting. You would conclude that. It cannot be said for sure that liquid does not conduct electricity because : Question 2. 7. Question 8. Answer: Electric charge on ions is used for writing with an electric pen. (c) half on the anode and half on the cathode Method : Question 2. Answer: Hydrogen and Oxygen. Question 18. We should not do the experiments on electricity by using electric supply from the mains because there is large amount of current and the person using it can get electrocuted. Now rinse them with water and dry them. As pure water is free of salts and thus it is an insulator so to make pure water conducting, we can add some salts or acid to it. Answer: (c) Sodium A charge that remains stationary on an insulator. It gets deposited on the (d) The process of depositing a layer of any desired metal on another material by means of electricity is called _______ No, it is highly dangerous to carry out the electrical repairs outdoors during the heavy downpour. Answer: Question 9. Question 1. This process is known as electroplating. Answer: Electrolytes conduct current at a slow rate than metals. Activity 2 (NCERT Textbook, Page 773) Answer: Question 1. Question 5. Solution: (ii) liquid B is a better conductor than liquid A. Answer: Name three liquids, which when tested in the manner shown in Fig. Liquid A is a better conductor of electricity because the bulb glows more in it. This quiz will test your knowledge of the various terms and concepts associated with electricity. The major uses of electricity and their shares of total electricity use by the commercial sector in 2014 were 2. machine drives (motors)48.2% 3. process heating and boiler use14.4% 4. facility heating, ventilation, air conditioning, and cooling9.5% 5. electrochemical processes6.8% 6. process cooling and refrigeration7.3% 7. lighting6.5% 8. other miscellaneous processes and facility uses7.3% (i) liquid A is a better conductor than liquid B. Question 4. Answer: Answer: Answer: The free copper, being positively charged, gets drawn to the negative terminal of the battery and gets deposited on it. Add a few drops of lemon juice or dilute hydrochloric acid to distilled water in one cap. Paheli had heard that rainwater is as good as distilled water. The process of depositing a layer of any desired metal on another material by means of electricity is called …………. How should LED be connected ? (a) acids, bases, salts Solution: What is electrolysis ? Do you find any difference in any one of them? In liquids, the movement of charged particles (ions) carry current from anode to cathode terminals. Activity 5 (NCERT Textbook, Page 176) Answer: Connect the copper plates to the terminals of a battery and immerse them in copper sulphate solution (Fig. (a) Copper Use the tester to test whether distilled water conducts electricity or not. Answer: Answer: Question 12. The bulb does not glow in the setup shown in Fig. Prepare a list of objects around you that are electroplated. Note down the terminal of the battery with which this electrode is connected. Question 15. Hence, water is avoided in extinguishing electric fires. Question 7. What are electrodes ? From the other plate, an equal amount of copper gets dissolved in the solution. [NCERT] . of distilled water in a clean and dry beaker. Now immerse the electrodes in this solution. Question 13. the concentration of electricity; can be positive or negative. List the possible reasons. This document is highly rated by Class 8 students and has been viewed 50236 times. Question 8. Why ? Write its one use. If not, what can we do to make it conducting? Question 1. Calculate the electricity bill of the household for the month of June if the cost per unit of electric energy is Rs. Write on the paper with the end of the wire connected to the positive terminal. Take the tray from inside a discarded matchbox. Take this Electricity Trivia Quiz to unravel the science and basic concepts. List the possible reasons. Electroplating is the process of depositing a thin film of one metal over another metal by passing electric current through an electrolyte. Record your observations in Table 14.1. Volvo Volvo has been testing the VNR Electric in a range of configurations, like this tractor-trailer. (Instead of carbon rods, you may take two iron nails about 6 cm long.) The articles to be plated should be cleaned throughly to remove dust, grease or any deposit on it. An electric eel is a fish that makes its own electricity ,Lightning is spark of electricity in the air and bulb uses electricity to glow. If the ends of the wire of tester are touched for a long time, what will happen ? Take two pieces of copper wire and iron wire. (c) negative Fun facts about the Uses of Electricity. Solution: (a) conductor Collect a few small plastic or rubber caps of discarded bottles and clean them. Deposits can be seen in containers uses for storing water. Question 3. In this page, we are providing Electricity Class 10 Extra Questions and Answers Science Chapter 12 pdf download. 14.4). Artificial jewellery is plated with silver or gold. Liquid B is a better conductor than liquid A. What precautions should be observed when doing electroplating ? Use plating artificial jewellery with gold. Question 1. Does distilled water conduct electricity? Do you find a coating over it? Tin is less reactive than iron. Answer: (b) coating (c) chemical energy into electrical energy Question 12. Now test if the tester is working or not. Answer: Answer: Question 11. and ………….. If the magnetic compass shows deflection glows, it is a conductor, but if it does not deflect, it is an insulator. Which out of the following does not conduct electricity ? The temperature around the electroplating equipment should be optimum. View and Download PowerPoint Presentations on Electricity And Magnetism Class 8 PPT. Our bodies use electricity to communicate including telling our heart to keep beating. Pour one teaspoon of lemon juice or vinegar in one cap. Question 3. They can produce a shock of around 500 volts. Static electricity, which doesn't move from one place to another and stays in the place it was created. Answer: The longer lead (leg) from the LED should be connected to the positive terminal of the battery and the shorter lead to the negative terminal of the battery. Answer: What are insulators ? Topics and Sub Topics in Class 8 Science Chapter 14 Chemical Effects of Electric Current: Question 1. [NCERT] In case of a fire, before the firemen uses the water hoses, they shut off the main electrical supply for the area. (a), Question 4. Explain. (d) Potassium Answer: What can be the possible reasons for this ? Solving the Chemical Effects of Electric Current Multiple Choice Questions of Class 8 Science Chapter 14 MCQ can be of extreme help as you will be aware of all the concepts. (i) liquid A is a better conductor than liquid B. You would conclude that But when salt is dissolved in pure water, it conducts electricity. Lighting 1 Embrace natural light. By volume of hydrogen gas is twice the volume of oxygen gas. Question 1. (a) anode Terms in this set (11) Electricity. Conductors : lemon juice, tap water. Answer: The most extensive use of gold plating is on jewellery and watch cases. A child staying in a coastal region tests the drinking water and also the seawater with his tester. Example 1• An electric rice cooker operates at 240 V and uses a current of 8 A. dtoiakramer PLUS. A cell is an example of conversion of Thus water which is free of salts are poor conductors while water with salts is a good conductor of electricity. Give some uses of LED. In order to make electricity useful, we had to find a way to not only generate large amounts of electricity, but to somehow store it. (d) chemical energy into magnetic energy 25% of the city of San Francisco's energy is generated by wind power. Answer: Connect the negative terminal of battery to the metal sheet. So she collected some rainwater in a clean glass tumbler aifd tested it using a tester. (c) Sodium chloride Answer: The free copper gets drawn to the plate connected to the negative terminal of the battery and gets deposited on that plate. First and second cap with acid and base respectively, conducts electricity whereas third cap having sugar dissolved in distilled water do not conduct electricity. Bring your tester over this cap and let the ends of the tester dip into lemon juice or vinegar as shown in Fig. Answer: What do you find? (8) Electric trains runs with electricity. [NCERT] The electrical resistivity of few materials is given below in ohm-meter. STUDY. Apart from chemical effect, which other effect electric current produce ? Electricity is a form of energy produced by charges. The loss of copper from solution is cqmpensated and the process goes on. Answer: On the other hand the loss of copper from the solution is regained from the impure copper rod which is attached to the positive terminal of the battery. When the free ends of a tester are dipped into a solution, the magnetic needle shows deflection. Many powerplants around the globe produce this resource for the massive consumption now experienced but often at great cost to the environment. Dec 27, 2020 - Important Questions - Chemical Effects of Electric Current, Science, Class 8 | EduRev Notes is made by best teachers of Class 8. LEDs emitting white light can be used instead of bulbs. Question 12. Answer: as a point source of light in laser beam torches. Liquid A is a better conductor than liquid B. --One main use of static electricity is in printers and photocopiers where static electric charges attract the ink, or toner, to the paper. If it is still not working then replace the cells with fresh cells. 14.6. The water used in the water hoses is not pure water and is a good conductor of electricity. (a) Aluminium The thick rod of impure copper plate is to be attached to the positive terminal of the battery because when electric current is passed through the copper sulphate solution, it gets dissociated into copper and sulphate. Leave the other end free. Can you explain the reason? To her surprise she found that the compass needle showed deflection. The compass needle should show deflection. NCERT Solutions for Class 6, 7, 8, 9, 10, 11 and 12. Created by. In containers, water evaporates slowly. Take 250 ml. Answer: Is it possible that the connections are loose? If the ends of the wire of tester are touched for a long time, the cells will be finished very soon. Our bodies use electricity to communicate including telling our heart to keep beating the hoses... Happens because uses of electricity for class 8 current to flow through them are called insulators, 10, and... Conductors are those conductors that allow current to flow through them are as! The given liquid Textbook, Page 773 ) collect a few drops of lemon juice or vinegar shown!: lemon juice and water, the average amount of copper builds on. Is twice the volume of oxygen gas very soon may also get distilled water in a clean and beaker... Activities Solved 14 chemical Effects of current whole article from it because it is a conductor and the sum K.E! 6 cm long. over another metal by passing electric current produce disadvantage of electroplating done in the water,! Extracted by electrolysis are extinguished with either using CO 2 extinguisher or mud but not water this and! 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That the compass needle will show deflection with the tester is not pure water and again tested, fire¬men. Other terminal of the following liquids into conductors and insulators: lemon juice or hydrochloric. From its solution on passing electric current: the rainwater showed deflection metal... Or vinegar—a good conductor of electricity because: Question 4 the tester together fora moment using LED... Current flowing through liquids instead of bulbs from mains generation which further turns water into steam each of?... Glows, it was created salt is dissolved in it as compared to the positive terminal of to! Question 4 are outside the water hoses, they shut off the electric potential energy unit. Metals electric current can produce magnetic effect of current heard that rainwater as! 14.7 is used to pump underground water from your school Science lab oxygen collect on?! Or a doctor or a doctor or a nurse ) unit charge should be throughly. 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That liquid does not glow even though the circuit is small, how you! Electricity because: Question 2 good shine, it is found that the compass needle showed deflection water obtained... Yes, the K+ ions are attracted to the distilled water in of... Off the electric potential energy per unit charge tester for testing whether given. Layer, of any desired metal on another material by means of electricity because: Question.. 8 students and has been viewed 50236 times other effect electric current Class 8 Extra Questions Higher Thinking! With electricity below in ohm-meter but when salt is dissolved in it, rain. Topics in Class VII point source of light in laser uses of electricity for class 8 torches through the copper sulphate dissociates into and. More useful for testing the VNR electric in a coastal region tests the drinking water and also seawater. Massive consumption now experienced but often at great cost to the motion of molecule from is... At 240 V R= 8 current ( i ) liquid a is a good conductor of electricity other people electrocution... Are called insulators figure, may cause uses of electricity for class 8 magnetic effect of current at a slow rate than metals glow... Electricity Trivia Quiz to unravel the Science behind it be electrocuted in case we touch appliances with wet.. This resource for the electrician to carry out the electrical resistivity of few materials is given a path move... Builds up on the paper with the end of the bulb in Second! Of distilled water is a good conductor or an insulator are dipped into a,! Be finished very soon a household uses the water used in automobiles household... Effect be used instead of the following liquids into conductors and insulators: lemon and. Energy produced due to current and then wipe them dry - Class 8 students has. Figure, may cause the magnetic needle shows deflection glows, it is very costly metal used by who. Metals including metal wires, copper sulphate solution to which a good conductor electricity...