Question Text
Question 1 :
An observer standing at the seacoast observes 54 waves reaching the coast per minute. If the wavelength of the waves is 10 m, its velocity is-<br>
Question 2 :
A block of mass m is attached to one end of a mass less spring which is suspended vertically from a fixed point. The mass is held in had so that the spring is neither stretched nor compressed. Suddenly the support of the hand is removed. The lowest position attained by the mass during oscillation is 4 cm below the point, where is was held in hand. The amplitude of the oscillation is
Question 3 :
The intensity of sound after passing through a slab decreases by 20{tex} \% {/tex} . On passing through two such slabs, the intensity will decrease by
Question 4 :
A mass {tex} M {/tex} attached to a spring oscillates with a period of {tex}2{/tex} seconds. If the mass is increased by {tex}2 \mathrm { kg } {/tex} the period increases by {tex}1{/tex} second. The initial mass {tex} M {/tex} will be