This set of Engineering Physics Multiple Choice Questions & Answers (MCQs) focuses on “Superposition of Waves”.

1. Which is different from others by units?

a) Phase difference

b) Mechanical equivalent

c) Loudness of sound

d) Poisson’s ratio

View Answer

Explanation: Of all the given quantities, Poisson’s ratio has no units.

2. The waves, in which the particles of the medium vibrate in a direction perpendicular to the direction of wave motion, is known as

a) Transverse waves

b) Longitudinal waves

c) Propagated waves

d) Magnetic waves

View Answer

Explanation: In transverse waves, particles of the medium vibrate in a direction perpendicular of the wave

3. The waves produced by a motor boat sailing in water are

a) Transverse

b) Longitudinal

c) Longitudinal and transverse

d) Stationary

View Answer

Explanation: Transverse waves are generated on the water surface. Inside water longitudinal waves longitudinal waves are produced due to vibrations of the rudder.

4. For a wave propagating in a medium, identify the property that is independent of the others.

a) Velocity

b) Wavelengths

c) Frequency

d) All these depend on each other

View Answer

Explanation: Wave velocity=frequency×wavelength

Frequency remains unchanged while velocity and wavelength and interdependent.

5. A boat at anchor is rocked by waves, whose crests are 100m apart and velocity is 25m/s. The boat bounces up once in every

a) 2500s

b) 75s

c) 4s

d) 0.25s

View Answer

Explanation: ʎ=100m, v=25m/s

T=ʎ/v=100/25=4s.

6. A transverse wave passes through a string with the equation

y=10sinπ(0.02x-2t)

Where x is in metres and t in seconds. The maximum velocity of the particles in wave motion is

a) 63m/s

b) 78m/s

c) 100m/s

d) 121m/s

View Answer

Explanation: y=10sinπ(0.02x-2t)

u=dy/dt=-20πcosπ(0.02x-2t)

u

_{max}=20π=63m/s.

7. If equation of a sound wave is

y=0.0015sin(62.8x+314t)

Then its wavelength will be

a) 0.1unit

b) 0.2units

c) 0.3unit

d) 2unit

View Answer

Explanation: y=0.0015sin(62.8x+314t)

y=asin(2π/ʎ x+2π/T t)

2π/ʎ=62.8

ʎ= (2×3.14)/62.8=0.1unit.

8. The plane wave is described by the equation

y=3cos(x/4-10t-π/2),

Where c is in meters and t in seconds. The maximum velocity of the particles of the medium due to this is

a) 30m/s

b) 3π/2 m/s

c) ¾ m/s

d) 40m/s

View Answer

Explanation: y=3cos(x/4-10t-π/2)

u=dy/dt=30sin(x/4-10t-π/2)

u

_{max}=30m/s.

9. The equation of wave is given by

y=10sin(2πt/30+α)

If the displacement is 5cm at t=0, then the total phase at t=7.5s will be

a) π/3rad

b) π/2rad

c) 2π/5rad

d) 2π/3rad

View Answer

Explanation: y=10sin(2πt/30+α)

At t=0, 5=10sinα or sin α=1/2

α=π/6

Total phase at t=7.5s,

φ=(2π×7.5)/300+π/6=π/2+π/6=2π/3.

10. If two sound waves having a phase difference of 60°, then they will have a path difference of

a) ʎ/6

b) ʎ/3

c) ʎ

d) 3ʎ

View Answer

Explanation: ∆φ=60°=π/3

∆x=ʎ/2π×∆φ=ʎ/2π×π/3=ʎ/6.

**Sanfoundry Global Education & Learning Series – Engineering Physics.**

To practice all areas of Engineering Physics, __here is complete set of 1000+ Multiple Choice Questions and Answers__.