(English Medium) ICSE Class 10 - CISCE Question Bank Solutions for Physics

Name a common device that uses electromagnets.

Name the device used to protect the electric circuits from over loading and short circuit. On what effect of current does it work?

A fuse is always connected in the live wire of the circuit. Explain the reason.

Name two factors on which the internal resistance of a cell depends and state how does it depend on the factors stated by you.

A cell of e.m.f ε and internal resistance r is used to send current to an external resistance R. Write expressions for

1. the total resistance of circuit.
2. the current drawn from the cell.
3. the p.d. across the cell.
4. voltage drop inside the cell. 

Explain why the p.d across the terminals of a cell is more in an open circuit and reduced in a closed circuit. 

A cell is used to send current to an external circuit.

1. How does the voltage across its terminals compare with its e.m.f.?
2. Under what condition is the e.m.f. of a cell equal to its terminal voltage? 

How is the working of an electric bell affected, if alternating current be used instead of direct current?

The diagram below in Fig. 8.40 shows a cell of e.m.f. ε = 2 volt and internal resistance r = 1 ohm to an external resistance R = 4 ohm. The ammeter A measures the current in the circuit and the
voltmeter V measures the terminal voltage across the cell. What will be the readings of the ammeter and voltmeter when (i) the key K is open, (ii) the key K is closed. 

A battery of e.m.f 3.0 V supplies current through a circuit in which the resistance can be changed.
A high resistance voltmeter is connected across the battery. When the current is 1.5 A, the voltmeter reads 2.7 V. Find the internal resistance of the battery. 

A cell of e.m.f. 1.8V and internal resistance 2Ω is connected in series with an ammeter of resistance 0.7Ω and a resistor of 4.5Ω as shown in Fig. 

1. What would be the reading of the ammeter?
2. What is the potential difference across the terminals of the cell? 

A battery of e.m.f. 15 V and internal resistance 3 ohm is connected to two resistors of resistances 3 ohm and 6 ohm is series Find:
(a) the current through the battery
(b) the p.d. between the terminals of the battery. 

A cell of e.m.f. ε and internal resistance 𝔯 sends current 1.0 A when it is connected to an external resistance 1.9 Ω. But it sends current 0.5 A when it is connected to an external resistance 3.9 Ω. Calculate the values of ε and 𝔯.

Describe one experiment to demonstrate the phenomenon of electromagnetic induction.

1. What kind of energy change takes place when a magnet is moved towards a coil having a galvanometer at its ends?
2. Name the phenomenon.

In which of the following case does the electromagnetic induction occur?
The current is stopped in a wire held near a loop of wire .

In which of the following case does the electromagnetic induction occur?

A magnet is moved through a loop of wire .

In which of the following case does the electromagnetic induction occur?

A loop of wire is held near a magnet.

Name and state the law which determines the direction of induced current.

or

State Fleming’s right-hand rule.