Force, Friction...

When a pencil is thrown upwards, then its speed goes on decreasing, because of:

Drag force is applied by which of the following and in which direction?

If the amplitude of a vibration is doubled then the loudness of the sounds will become:

Frequency of vibration is directly proportional to___ of sound.

If we strike a wooden table with a steel spoon lightly we hear a feeble sound but if we hit the wooden table hard with steel spoon, a loud sound is heard because:

Which one of the following statements is correct?

(i) Loudness of sound is directly proportional to the square of amplitude vibrations.
(ii) Sound can travel through vacuum.
(iii) Speed of sound is maximum in solids.
(iv) The outer part of ear is called ear canal.

Which one of the following is not a bone of ear?

Unit of measuring loudness is:

In order to increase the loudness of a sound we have to: