When the pitch of note produced by a harmonium is lowered, then the wavelength of the note:

A. decreases

B. first decreases and then increases

C. increases

D. remains the same

The sound waves travel fastest:

A. in solids B. in liquids

C. in gases D. in vacuum

The speeds of sound in four different media are given below. Which of the following is the most likely speed in m/s with which the two under water whales in a sea talk to each other when separated by a large distance?

A. 340 B. 5170

C. 1280 D. 1530

The velocities of sound waves in four media P. Q, R and S are 18,000 km/h, 900 km/h, 0 km/h, and 1200 km/h respectively. Which medium could be a liquid substance?

A. P B. Q

C. R D. S

Which of the following can produce longitudinal waves as well as transverse waves under different conditions?

A. water B. TV transmitter

C. slinky D. tuning fork