A boat moves in still water with a velocity which is `k` times less than the river flow velocity. Find the angle to the stream direction at which the boat should be rowed to minimize drifting.

The force of resistance encountered by water on a motor boat of mass m going in still water with velocity v is proportional to the velocity vdot At t=0 when its velocity is v_0, then engine shuts off. Find an expression for the position of motor boat at time t and also the distance travelled by the boat before it comes to rest. Take the proportionality constant as k > 0.

A boat is moving with a velocity (3hati-4hatj) with respect to ground. The water in river is flowing with a velocity (-3hati-4hatj) with respect to ground. What is the relative velocity of boat with respect to river?

A man can swim in still water ast a speed of 3 km/h. He wants to cross a river that flows at 2 km/h and reach the point directly oposite to his starting point. A. In which diretionshoeld he try to swim (that is, find the angle his body makes wilth the river flow)? b. How much time will he take to cross the river if the river is 500 m wide?

A motor boat whose speed is 18km/hr in still water takes 1hour more to go 24km upstream than to the return downstream to the same spot. Find the speed of the stream.

The temperature of H_2 at which the rms velocity of its molecules is seven times the rms velocity of the molecules of nitrogen at 300 K is :

A 400 m wide river is flowing at a rate of 2.0 m s^-1 . A boat is sailing with a velocity of 10 m s^-1 with respect to the water, in a direction perpendicular to the river. (a) Find the time taken by the boat to reach the opposite bank.

A flat dielectric disc disc of radius R carries an excess charge on its surface. The surface charge density is sigma . The disc rotates about an axis perpendicular to its plane passing through the center with angular velocity omega . Find the magnitude of the torque on the disc if it is placed in a uniform magnetic field whose strength is B which is directed perpendicular to the axis of rotation