Question

Two blocks (m and M) are arranged as in
figure. There is friction between ground
and M only and other surfaces are
frictionless. The coefficient of friction
between ground and M is u = 0.25. The
maximum ratio of m and M (m/M) so that
the system remains is at rest -
u = 0.25
M
ml
ها | دن دن
(B)
(D) none of these
(C) 3

Answer 1

Answer:

A woman with a mass of 60kg climbs a flight of stairs.

a) What is her weight in Newtons?

b) What is the magnitude of the force her legs exert in order to climb the stairs?

c) The top of the stairs is 3m higher than the bottom. Calculate the work she does in climbing the stairs.

d) Calculate the increase in her gravitational potential energy.

She takes 5s to climb the stairs. Calculate

e) her average kinetic energy during her ascent,

f) the power, in Watts, she must have to carry this out.

(Take the acceleration due to gravity to be 10m/s2)