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

Why soft iron is preferred to be used as the core of the electromagnet of an electric bell?

What is an electromagnet? What do you know about the simplest form of an electromagnet?

Draw a labelled diagram to make an electromagnet from a soft iron bar. Mark the polarity at its ends in your diagram. What precaution would you observe while making it?

You have been provided with a solenoid AB.

(i) What is the polarity at end A?
(ii) Give one advantage of an electromagnet over a permanent magnet.

The diagram shows a rectangular coil ABCD, suspended freely between the concave pole pieces of a permanent horseshoe magnet, such that the plane of the coil is parallel to the magnetic field.

1. State your observation when the current is switched on.
2. Give an explanation for your observation in (i).
3. State the rule, which will help you to find the motion of rotation of the coil.
4. In which position will the coil ultimately come to rest?
5. State four ways of increasing the magnitude of force acting on the coil.

An element P disintegrates by α-emission and the new element suffers two further disintegration, both by β-emission, to form an element Q. Explain that fact P and Q are isotopes.

Pendulums A, B, C and D are tied to a flexible string PQ and are at rest. Pendulum C is disturbed. Which of the following statements is true?

(a) Calculate the total resistance across AB.

(b) If a cell of e.m.f 2.4 V with negligible internal resistance is connected across AB then calculate the current drawn from the cell.

1. Name the phenomenon illustrated by the above experiment.
2. Why is a loud sound heard at this particular length?
3. If the present tuning fork is replaced with a tuning fork of higher frequency, should the length of the air column increase or decrease to produce a loud sound? Give a reason.

Study the diagram:

1. Calculate the total resistance of the circuit.
2. Calculate the current drawn from the cell.
3. State whether the current through 10 Ω resistor is greater than, less than or equal to the current through the 12 Ω resistor.

Name the radiations that are emitted during the decay of a nucleus, which has highest penetrating power?

Does the emission of gamma radiation result in a change in the mass number?

A radioactive nucleus X emits an alpha particle followed by two beta particles to form nucleus Y.

1. With respect to the element X, where would you position the element Y in the periodic table?
2. What is the general name of the elements X and Y?
3. If the atomic number of Y is 80 then what is the atomic number of X?

Name the type of energy (kinetic energy K or potential energy U) possessed in the following case:

A moving cricket ball

Name the type of energy (kinetic energy K or potential energy U) possessed in the following case:

A compressed spring

Name the type of energy (kinetic energy K or potential energy U) possessed in the following case:

A moving bus

Explain the meaning of the term internal resistance of a cell.

The diagram in Figure shows a cell of e.m.f. ε = 4 volt and internal resistance r = 2 ohm connected to an external resistance R = 8 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

1. the key K is open, and
2. the key K is closed

A battery of e.m.f. 6.0 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 3 A, the voltmeter reads 5.4 V. Find the internal resistance of the battery.

A radioactive source emits three type of radiations.

From which part of the atom do these radiations come?