Electricity is the flow of electric charge that powers devices and makes things work.
Important Parts of Electricity:
- Electric Current: The flow of electric charge, measured in Amps (A).
- Voltage: The force that pushes the electric charge, measured in Volts (V).
- Resistance: The opposition to the flow of current, measured in Ohms (Ω).
- Ohm's Law: V = I × R – Voltage = Current × Resistance.
- Power: The amount of energy used, calculated by P = V × I (measured in Watts).
Types of Current:
- DC (Direct Current): Flows in one direction (like from a battery).
- AC (Alternating Current): Reverses direction (like in home electricity).
Practice Questions PDF
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Questions on Electricity
Showing 91–120 of 12891.When resistors are connected in series, the total resistance is: 92.Which of the following materials has the lowest electrical resistivity? 93.The SI unit of electrical resistance is: 94.The resistance of a conductor depends on: 95.According to Ohm's Law, if the potential difference across a conductor is doubled, the current flowing through it will: 96.Ohm's Law states the relationship between: 97.A device used to measure potential difference across two points in an electric circuit is called: 98.The SI unit of potential difference is: 99.The work done in moving a unit charge from one point to another in an electric circuit is called: 100.A device used to measure electric current in a circuit is called: 101.The SI unit of electric current is: 102.The flow of electric charge is known as: 103.Which of the following is an example of an electrical insulator? 104.The SI unit of electric charge is: 105.What determines the rate at which energy is delivered by a current? 106.An electric iron of resistance 20 Ω takes a current of 5 A. Calculate the heat developed in 30 s. 107.Compute the heat generated while transferring 96000 coulomb of charge in one hour through a potential difference of 50 V 108.Why does the cord of an electric heater not glow while the heating element does? 109.What are the advantages of connecting electrical devices in parallel with the battery instead of connecting them in series? 110.Why are coils of electric toasters and electric irons made of an alloy rather than a pure metal? 111.Let the resistance of an electrical component remains constant while the potential difference across the two ends of the component decreases to half of its former value. What change will occur in the current through it? 112.Will current flow more easily through a thick wire or a thin wire of the same material, when connected to the same source? Why? 113.On what factors does the resistance of a conductor depend? 114.What is meant by saying that the potential difference between two points is 1 V? 115.Name a device that helps to maintain a potential difference across a conductor. 116.Calculate the number of electrons constituting one coulomb of charge. 117.Define the unit of current. 118.What does an electric circuit mean? 119.How much energy is given to each coulomb of charge passing through a 6 V battery? 120.What is the maximum resistance which can be made using five resistors each of 1/5 Ω ?