Water in a canal,6 m wide and 1.5 m deep,is flowing with a speed of 10km/h.How much area will it irrigate in 30minutes,if 8cm of standing water is needed?

A farmer connects a pipe of internal diameter 20cm from a canal into a cylindrical tank in her field,which is 10 m in diameter and 2 m deep.If water flows through thr pipe at the rate of 3 km/h,in how much time will the tank be filled?

A man can swim with a speed of 4.0 km/h in still water. How long does he take to cross a river 1.0 km wide if the river flows steadily at 3.0 km/h and he makes his strokes normal to the river current? How far down the river does he go when he reaches the other bank?

A police van moving on a highway with a speed of 30 km h_ 1 fires a bullet at a thief’s car speeding away in the same direction with a speed of 192 km h^-1 . If the muzzle speed of the bullet is 150 m s^1 with what speed does the bullet hit the thief’s car ? (Note: Obtain that speed which is relevant for damaging the thief’s car).

:A 10 kW drilling machine is used to drill a bore in a small aluminium block of mass 8.0 kg. How much is the rise in temperature of the block in 2.5 minutes, assuming 50% of power is used up in heating the machine itself or lost to the surroundings. Specific heat of aluminium = 0.91 J g^-1 K^-1 .

Water flows through a circular pipe whose internal diameter is 2 cm at the rate of 0.7 m per second into a cylindrical tank, the radius of whose base is 40 cm. By how much will the level of water rise in the tank in half an hour.

A proton enters a magnetic field of flux density 1.5Wb/m^2 with a speed of 2×10^7 m/s at angle of 30^o with the field. Find the force on the proton .

In a chamber , a uniform magnetic field of 6.5G(1G=10^−4T) is maintained. An electron is shot into the field with a speed of 4.8×10^6m/s normal to the field. Determine the radius of the circular orbit.

A plane is in level flight at constant speed and each of its two wings has an area of 25 m^2 . If the speed of the air is 180 km/h over the lower wing and 234 km/h over the upper wing surface, determine the plane’s mass. (Take air density to be 1 kg m^-3) .

A swimmer can swim with Velocity of 10 km/h. w.r.t, the water flowing in a river with velocity of 5 km/h. In what direction should he swim to reach the point on the other bank just opposite to his starting point?