Question

Q1 A moving body of mass 20 kg has 40 Joules of kinetic energy. Calculate its speed.

Q2 A man carrying a load of 20 kg climbs 4 m in 10 secs. Calculate the work done and power. Take g-10.

Answer 1

1)K.E.=1/2mv^2
40=1/2×20×v^2
40=10v^2
v^2=4
V=2m/s

Answer 2

Answer:

1) Speed= 2 m/s

2) work done= 800 J

Power = 80 W

Explanation:

1) K.E. =1/2mv^2

40=1/2x20xv^2

40=10v^2

v^2=40/10

v^2=4

v=2 m/s

2)P.E.=mgh=work done

P.E.=20x10x4

P.E.=800 J

Power= work done/time

Power= 800/10

Power = 80 W