Which type of wave propaates in liquid? Explain . 

The type of wave that propagates in a liquid is called a mechanical wave. Mechanical waves are waves that require a medium to propagate, meaning they need a substance to travel through. In the case of liquid, such as water, mechanical waves can travel through it.

There are two primary types of mechanical waves that can propagate in a liquid: transverse waves and longitudinal waves.

1. Transverse Waves: In a transverse wave, the particles of the medium move perpendicular to the direction of wave...

The blocks A and B have equal masses. The surface of A is smooth but that of B has a friction coefficient of 0.1 with the floor. Block A is moving at a speed of 10 m/s towards B which is kept at re...

a) In a lab frame of reference,

    Velocity of center of mass is given by,

       v'=(mv_OA+ mv_OB)/2m

Now, in center of mass frame of reference,

Since, there will be perfectly elastic collision. After collision, they exchange their velocity.

In lab frame of reference,

Deceleration due to the friction = µg

From kinematics we have,

V_F=V_B- µgt

Since the final velocity of B is zero, we get t=10s.

Distance travelled d is given by,

d = V_Bt - (µgt²)/2

Inserting given...

Why are sound easier to hear at night than at day time?

Due to the refraction of sound, we can hear sounds easily at night than during clear days.

On a clear day, the lower layer of the atmosphere is hotter than the layers above. Since sound travels faster in a hotter medium, its speed is greater near the surface. As a result, the waves are bent away from the surface. Thus, the intensity of the sound waves diminishes and does not seem to travel a long distance. On a clear night, the lower layer of the atmosphere is colder than the air above. Now,...