Question

A crane lifts a 450 kg concrete to the top of a 50 m building in 5 s.

Assuming g= 10 m/s
)
2
a) The potential energy of the concrete.
, calculate;
b) The power developed by the crane

Answer 1

Step-by-step explanation:

Given : m=600kg h=20 m

Time of operation t=2 min =120 s

Work done in lifting a box W=mgh=600×10×20=120000

Power required P=

t

W

=

120

120000

=1000 watts