Science Class 7th

371. Time taken to complete one vibration is called?

A) Second

B) Vibration

C) Time period

D) None

372. Number of vibrations/ waves per second is called?

A) Time period

B) Frequency

C) Amplitude

D) None

373. The shorten the wave length , the ______ frequency.

A) Higher

B) Lower

C) Neither higher nor lower

D) None of these

374. Unit of frequency is?

A) Meter

B) Second

C) Hertz

D) None

375. Distance traveled by wave in one second is called _____ of wave.

A) Frequency

B) Velocity

C) Acceleration

D) None

376. SI unit for measuring velocity is?

A) m/s

B) m/s2

C) m

D) None

377. Characteristic of sound by which a shrill sound can be distinguished from a grill sound is called?

A) Pitch of sound

B) Loud sound

C) Grave sound

D) None

 

378. Pitch of sound will be high if ______ is high.

A) Frequency

B) Wave

C) Time period

D) None

379. Frequency of ________ sound is greater hence high pitch and shrill sound.

A) Children

B) Men

C) Women

D) Both ‘a’ and ‘c’

380. Characteristic of sound by which a loud and faint sound can be distinguished is called?

A) Pitch

B) Frequency

C) Loudness of sound

D) None

381. Loudness depends upon?

A) Area of vibrating body

B) Amplitude of vibrating body

C) Distance from vibrating body

D) All of these

382. Which has more energy?

A) Soft sound

B) Loud

C) Faint

D) None

 

383. Loudness is measured in?

A) Kg

B) Decibels (dB)

C) Meter

D) None

384. Unwanted and loud sounds are called?

A) Music

B) Noise

C) Sound

D) All of these

385. A sound of less than 20 Hz, is called?

A) Infra sound

B) Ultra sound

C) Noise

386. Sound above 20000 Hz is called?

A) Infra sound

B) Ultra sound

C) None

387. Sound above 20,000 Hz and below 20 Hz is?

A) Audible

B) Inaudible

C) Sometimes audible

D) None

388. Silent whistle frequency for calling dog lies between?

A) 2000 Hz to 50,000 Hz

B) 30 to 60000

C) 50000 to 5000

D) None

 

389. Mouse audible frequency range is?

A) 5000 – 6000

B) 1000 – 100000

C) 6000 – 50000

390. Cow audible frequency range is?

A) 23 – 35000

B) 5000 – 60000

C) 25000 – 36668

D) None