Mechanical Waves

Q.

A mechanical wave needs a material medium for propagation.

1. True

2. False

Q.

Sound is produced because of _______ of a body.

1. Charge

2. Rotations

3. None of these

4. Vibrations

Q. Give two examples to show that sound is produced due to the vibration of objects.

Q. When a drum is beaten by a stick, a sound is heard due to

1. 
   heating of the membrane
2. 
   vibration of the stick
3. 
   vibration of the membrane
4. 
   freezing of the membrane

Q.

To and fro motion of an object is also known as:

1. Oscillatory motion

2. Circular motion

3. Accelerated motion

4. None of the above

Q.

Which of the following is/are true about a mechanical wave?

1. A disturbance that propagates through the medium

2. An oscillation that propagates through the medium

3. It is accompanied by energy transfer

4. All of these

Q.

Why can light travel in vacuum, whereas sound can not do so ?

Q.

Question 3 (a)
State whether the following statement is true or false.
(a) Sound cannot travel in vacuum.

Q. Can sound travel through vacuum? Describe an experiment to explain your answer.​

Q.

A rubber band tied between two ends is stretched and then left. A sound is heard due to:

1. the to and fro motion i.e., vibration of the band

2. the elastic nature of the band

3. both elastic nature as well as vibrations in the string

4. none of these

Q. Are all periodic motions oscillatory? Explain.

Q. Are all periodic motions oscillatory? Explain.

Q.

Question 19
Two astronauts are floating close to each other in space. Can they talk to each other without using any special device? Give reasons.

Q.

The sound is produced because of _______ of a particle.

1. Vibrations

2. Rotations

3. Charge

4. None of these

Q. Sound cannot travel in:

1. Solids
2. Liquids
3. Gases
4. Vaccum

Q.

Vibration can be defined as the

1. stretching of a membrane

2. roughness of a membrane

3. circular motion of a membrane

4. to and fro motion of a membrane

Q. Which of these is not an example of mechanical wave?

1. Sound waves
2. Light waves
3. Seismic waves
4. Water waves

Q.

Sound travels in the form of _____.

1. both as waves and particles

2. particles

3. either particles or waves, depending on the medium

4. waves

Q. waves require a medium for their propagation.

1. Mechanical
2. Non-mechanical
3. Light

Q. Sound and light waves, both ______.

1. have the same speed
2. travel through vacuum
3. obey the laws of reflection
4. are forms of energy

Q.

Which of the following is/are properties of a wave?

1. A disturbance that propagates through the medium

2. An oscillation that propagates through the medium

3. It is accompanied by energy transfer

4. All of these

Q. The oscillations in copper disc in a magnetic field are highly damped. Why? Where does the vibrational kinetic energy of the copper disc disappear.

Q. There are a , number of devices in common use that change energy from one form to another. Name some devices that change.
sound energy into electrical energy