Question

A boy weighing 350N climbs up 30 steps, each 20cmhigh in 1 minute. Calculate :
(i) the work done, and
(ii) the power spent.
(Answers : (i) 2100J (ii) 35W )

Answer 1

Force - 350N

Distance - 0.2×30= 6 m

Time = 1 min = 60 s

_____________________

Work Done = Force × Displacement

= 350 ×6 = 2100 J

_____________________

Power = work/Time

= 2100/60 = 35 W

________________

Hope this helps ✌❤

Answer 2

$\mathcal{\blue{\underline{SOLUTION:-}}}$

Potential energy = mgh

Given that,

Weight = mg = 350 N

h = total height = height of one step x number of steps = 0.2m x 30 = 6m

So,

1). Work done = potential energy = mgh

W = 350 x 6

W = 2100 J

2). Power = W/t = 2100/60 = 35 W