Doors of a dam are 20m below the surface of water in the dam. If one door is opened what will be the speed of the water that flows out of the door ?
A light bulb is rated 100W for 220 V AC  supply of 50 Hz. Calculate (a) resistance  of the bulb. (b) the rms current through  the bulb.
The mass of the earth is 6 x 10²⁴ kg.  The distance between the earth and  the Sun is 1.5x 10¹¹ m. If the  gravitational force between the two  is 3.5 x 10²² N, what is the mass of  the Sun?
The masses of the earth and moon  are 6 x 10²⁴ kg and 7.4x10²² kg,  respectively. The distance between  them is 3.84 x 10⁵ km. Calculate the  gravitational force of attraction  between the two?
A ball falls off a table and reaches  the ground in 1s. Assuming g = 10  m/s², calculate its speed on reaching  the ground and the height of the  table.