Free MCQs & Online Quiz Practice for Exams

Q: When distance between source and listener increases intensity of sound?

A) Increases

B) Decreases

C) Remains same

D) Becomes Zero

Q: The intensity of a sound wave increases by 1000 W/m. What is this increase equal to in decibels?

A) 10

B) 20

C) 30

D) 40

Q: An echo occurs when a sound wave is

A) absorbed

B) transmitted

C) refracted

D) reflected

Q: Compared with a sound of 60 decibels a sound of 80 decibels has an intensity times greater

A) 100

B) 10

C) 1000

D) 10000

Q: The loudness of a sound is most closely related to its

A) frequency

B) period

C) wavelength

D) amplitude

Q: Various instruments sound different even when they play the same note due to difference in

A) pitch

B) loudness

C) quality

D) intensity

Q: Humans can hear sound that is

A) less than 20 Hz

B) between 20 Hz and 20 kHz

C) greater than 20 kHz

D) None

Q: The speed of sound on a warm day when the outdoor temperature is 38?C

A) 331 m/s

B) 345 m/s

C) 354 m/s

D) 362 m/s

Q: Minimum echo distance is reduced in

A) summer

B) winter

C) spring

D) autumn

Q: Which of the following cannot transmit sound?

A) solid

B) liquid

C) gas

D) vacuum

Q: The focal length of a convex lens is positive or negative?

A) Positive

B) Negative

C) Zero

D) Infinite

Q: An object placed at center of curvature of concave mirror produces an image that is?

A) Real and same size

B) Virtual and magnified

C) Real and diminished

D) Virtual and inverted

Q: Which mirror always produces a virtual image?

A) Concave

B) Convex

C) Plane

D) Concave at center

Q: Light bends when it passes from air to water due to?

A) Reflection

B) Refraction

C) Diffraction

D) Interference

Q: The magnification of a plane mirror is?

A) Zero

B) One

C) Greater than one

D) Less than one

Q: Principal focus of a concave lens is?

A) Real

B) Virtual

C) At infinity

D) Depends on lens thickness

Q: Which device uses total internal reflection?

A) Prism

B) Lens

C) Concave mirror

D) Convex mirror

Q: If the angle of incidence is 30? then the angle of reflection will be

A) 30?

B) 45?

C) 90?

D) 210?

Q: When d is the radius of curvature of a concave mirror. Real diminished image will be formed when the object is at

A) d₀>r

B) d₀=r

C) r>d₀>f

D) d₀=f

Q: The focal length of a convex mirror with radius of curvature 10 cm is

A) +10 cm

B) +5 cm

C) -10 cm

D) -5 cm