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.
An object thrown vertically upwards  reaches a height of 500 m. What was  its initial velocity? How long will the  object take to come back to the  earth? Assume g = 10 m/s²
The mass and weight of an object on  earth are 5 kg and 49 N respectively.  What will be their values on the  moon? Assume that the acceleration  due to gravity on the moon is 1/6th  of that on the earth.