The bullet hits the 50 cm thick wooden board with a speed of \( 108 \mathrm{~km} / \mathrm{h} \). What is the deceleration of the bullet, if it leaves the board after 3.5 s ?

(a) (i) State the principle of superposition of waves. (ii) Distinguish between standing and stationary waves. (b) Define the following terms as applied to sound waves (i) Interference and beating. (ii) resonance and fundamental frequence.

2. For how long must a force of 10 N act on a body at rest of mass 400 grams for said body to reach a speed of \( 20 \mathrm{~m} / \mathrm{s} \) ?

A train moving in the east direction accelerates from rest to \( 36 \mathrm{~km} / \mathrm{h} \) in 20 s . What is the average acceleration during that time interval?

The bullet hits the 50 cm thick wooden board with a speed of \( 108 \mathrm{~km} / \mathrm{h} \). What is the deceleration of the bullet, if it leaves the board after 3.5 s ?

The bullet hits the 50 cm thick wooden board with a speed of \( 108 \mathrm{~km} / \mathrm{h} \). What is the deceleration of the bullet, if it leaves the board after 3.5 s ?