List of top Physics Questions on Speed and velocity asked in IIT JAM BT

Rain is falling vertically with a speed of 40 $m s^{-1}$. Wind starts blowing with a speed of 16 $m s^{-1}$ in the west to east direction. How should a person, who is standing, hold his umbrella to avoid getting wet?
A man throws a ball vertically up in the air with an initial velocity v1 such that it reaches a height of 12 m with a speed of 12 m/s. If he throws the same ball vertically up with an initial velocity v such that it reaches a maximum height of 12 m. Calculate v1/v2 (up to 2 decimal places).

An ultrasound signal of frequency 50 KHz is sent vertically down into a medium. The signal gets reflected from a depth of 25 mm and returns to source 0.00005 seconds after it is emitted. The wavelength of the ultrasound signal in that medium is ............... cm.