A boy weighing 40 kgf climbs up a stair of 30 steps each 20 cm high in 4 minutes and a girl weighing 30 kgf does the same in 3 minutes.Compare:
(i)the work done by them.and
(ii)the power developed by them .

A Boy weighing 40 kg climbs up a stair of 30 steps each 20 cm high in 4 minutes and a girl weighing 30 kg does the same in 3 minutes. Compare: The power developed by them.

A boy of mass 40 kg climbs up a flight of 30 steps each 20 cm high in 2 min and a girl of mass 30 kg does the same in 1.5 min. Compare : (i) the work done, and (ii) the power developed by them (g = 10 m s^(-2) )

A boy weighing 350 N climbs up 30 steps.each 20 cm high in 1 minute .Calculte: (i)The work done ,and (ii)the power spent.

A man raises a box of mass 50 kg to a height of 2 m 10 s,while another man raises the same box to the same height in 50 s. (a)Compare :(i)the work done ,and (ii)the power developed by them . Take g=10 N kg^(-1)

IT takes 20 s for a person A of mass 50 kg to climb up the stairs. While another person B of same mass does the same in 15 s compare (i) work done (ii) power developed by the person A and B.

A boy mass 40 kg climbs up the stairs and reaches the roof at a height 8 m in 5 s. Calculate : (i)the force of gravity acting the boy . (ii) the work done by against the force of gravity . (iii)the power spent by the boy . (Take g=10 m S^(-2) )

Amit weighing 60 kgf climbs up a ladder of height 10 m in 15 minutes. Calculate the increase in his potential energy and the power spent by him. Take 1 kgf = 10 N.

A boy takes 3 minutes to lift a 20 litre water bucket from a 20 m deep well,while his father does it in 2 minutes ,(a)compare: (i)the work ,and (ii)power developed by them. (b)How much work rach deos?Take density of water = 10^(3) kg m^(-3) and g=9.8 N kg^(-1)

A boy weighing 60 kgf is wearing shoes with heel of area of cross section 20 cm^(2) , while a girl weighing 45 kgf is wearing sandals with heel of area of cross section 1.5 cm^(2) . Compare the pressure exerted on ground by their heels when they stand on the heel of one foot.

A uniform seesaw, 5m long, is supported at its centre. A boy weighing 40 kgf sits at a distance of 1 m from the centre of the seesaw. (i) To which class of lever does it belong ? (ii) Find where a girl of weight 20 kgf must sit on the seesaw so as the balance the weight of the boy.