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

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.

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.

Give one reason for the use of ultrasonic waves in echo depth sounding.

State two causes of energy loss in a transformer.

The V-I graph for a series combination and for a parallel combination of two resistors is shown in the figure below. Which of the two A or B. represents the parallel combination? Give reasons for your answer.

The music system draws a current of 400 mA when connected to a 12 V battery.

1. What is the resistance of the music system?
2. The music system if left playing for several hours and finally the battery voltage drops and the music system stops playing when the current drops to 320 mA. At what battery voltage does the music system stop playing?

Calculate the quantity of heat produced in a 20 Ω resistor carrying 2.5 A current in 5 minutes.

A battery of emf 12 V and internal resistance 2 Ω is connected with two resistors A and B of resistance 4 Ω and 6 Ω respectively joined in series.

Find:

1. Current in the circuit.
2. The terminal voltage of the cell.
3. The potential difference across 6Ω Resistor.
4. Electrical energy spent per minute in the 4Ω resistor.