At a hydroelectric power plant, the water pressure head is at a height of 300 m and the water flow available is `100 m^3s^-1`. If the turbine generator efficiency is 60%, estimate the electric power available from the plant `(g = 9.8 ms^-2)`.

The power of a motor pump is 5 kW. How much water per minute the pump an raise to height of 20 m ? Take g = 10ms ^-2 .

A pump on the ground floor of a building can pump up water to fill a tank of volume 30 m^3 in 15 min. If the tank is 40 m above the ground, and the efficiency of the pump is 30%, how much electric power is consumed by the pump ?

A stone dropped from the top of a tower of height 300 m high splashes into the water of a pond near the base of the tower. When is the splash heard at the top given that the speed of sound in air is 340 m s^-1 ? (g = 9.8 m s^-2)

The radius of curvature of a railway track at a place where the train is moving at a speed of 72 km h^-1 is 625 m.The distance between the rails is 1.5 m.Find the angle and the elevation of the outer rail so that there may be no side pressure on the rails. (g=9.8 m s^(-2)) .

A solenoid 60 cm long and of radius 4.0 cm has 3 layers of windings of 300 turns each. A 2.0 cm long wire of mass 2.5 g lies inside the solenoid (near its centre) normal to its axis, both the wire and the axis of the solenoid are in the horizontal plane. The wire is connected through two leads parallel to the axis of the solenoid to an external battery which supplies a current of 6.0 A in the wire. What value of current (with appropriate sense of circulation) in the windings of the solenoid can support the weight of the wire? g = 9.8 m s^-2 .

The stone of mass 100 g is suspended from the end of a weightless string of length 100 cm and is allowed to swing in a vertical plane.The speed of the mass is 2 m s^-1 when the string makes an angle of 60^@ with the vertical .Calculate the tension in the string at theta = 60^@ .Also,caculate the speed of the stone when it is in the lowest poition. (g=9.8 m s^(-2) ) .

Two narrow bores of diameters 3.0 mm and 6.0 mm are joined together to form a U-tube open at both ends. If the U-tube contains water, what is the difference in its levels in the two limbs of the tube ? Surface tension of water at the temperature of the experiment is 7.3xx 10^-2 N m^-1 '. Take the angle of contact to be zero and density of water to be 1.0xx 10^3 kg m^- 3 ( g = 9.8 m s^-2 ) .

The density of air in atmoshpere decreases with height and can be expressed by the relaton rho = rho_0e^(-alphah where rho_0 is the density at sea level , alpha is a constant and h is the height, Calculate the atmospheric pressure at sea level. Assume g to be constatn. The numerical values of constants are : g = 9.8 ms^-2 , rho_0 = 1.3 kg m^-3 , alpha = 1.2 xx 10^-4 m^-1

A tank containing water upto the height 15 m from the bottom of the tank. Find the speed and horizontal range of the water jet coming out through an orifice which is at 5 m above the bottom of the wtawer tank . {(Use g = 10 m s^-2)