(English Medium) ICSE Class 10 - CISCE Important Questions for Physics

A man playing a flute is able to produce notes of different frequencies. If he closes the holes near his mouth, will the pitch of the note produced, increase or decrease? Give a reason.

Two waves of the same pitch have amplitudes in the ratio 1 : 3. What will be the ratio of their : 
(i) intensities and
(ii) frequencies

(i) Define resonant vibrations. 
(ii) Which characteristic of sound, makes it possible to recognize a person by his voice without seeing him?

It is observed that during march-past we hear a base drum distinctly from a distance compared to the side drums.
(i) Name the characteristics of sound associated with the above obervation.
(ii) Give a reason for the above observation.

Two pendulums C and D are suspended from a wire as shown in the figure give below. Pendulum C is made  to oscullate by displaying it from its mean position. It is seen that D also starts oscillating. 

(i) Name the type of oscillation, C will execute.
(ii) Name the type of oscillation, D will execute.
(iii) If the length of D is made equal to C then what difference will you notice in the oscillations of D ?
(iv) What is the name of the phenomenon when the length of D is made equal to C ?

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?

Resonance is ______.

(a) Which one of the following graphs A or B shows free vibrations in a vacuum and which one shows free vibrations in a medium?

(b) How did you come to this conclusion.

1. Define pitch.
2. Two wires AB and CD of same length are stretched by same amount. Which wire will produce a sound of greater pitch on plucking?
3. Give a reason for your answer.

A change in amplitude of a sound wave is noticed.

1. Which characteristic of sound is affected due to the above change?
2. How is amplitude related to your answer to part (a) above?
3. What happens to the quality of the sound?

Two notes are produced from two different musical instruments, such that they have same loudness and same pitch. The produced notes differ in their ______.

A metal foot ruler is held at the edge of a table. It is pressed at its free end and then released. It vibrates.

1. Name the vibrations produced.
2. State one way to increase the frequency of these vibrations.

Which characteristic of sound is affected due to the larger surface of a school bell?

Calculate the distance covered by the Ultrasonic wave having a velocity of 1.5 kms^-1 in 14 s, when it is received after reflection by the receiver of the SONAR.

We are able to see the T.V. channels clearly when we set T.V. on auto-tuning.

1. Which phenomemon led to the clear visibility of the channels, due to auto-tuning?
2. Define the above phenomenon mentioned by you.
3. Give any one more example of this phenomenon.

When the stem of vibrating tuning fork is pressed on a table, the tabletop starts vibrating. These vibrations are definitely an example of ______.

Rohan conducted experiments on echo in different media. He observed that a minimum distance of 'x' meters is required for the echo to be heard in oxygen and 'y' meters in benzene. Compare 'x' and 'y'. Justify your answer.

Speed of sound in oxygen: 340 ms^-1

Speed of sound in benzene: 200 ms^-1

Name the waves used in SONAR.

In the above diagram Lata stands between two cliffs and claps her hands.

Determine the time taken by her to hear the first echo. Speed of sound in air 320 ms^-1.