Question

7. A body of mass to 2kg , is projected vertically
upward with velocity 2 m/s, the K. e of the
body just before Staicking the ground
a) 2 J
d) 8J
c) 4j
d) 8J​

Answer 1

Answer:

Applying energy conservation at time of projection, and returning at ground.

2

1

mu

2

=

2

1

mv

2

⟹u=v

It shows that particle is projected vertically upward with velocity of 2m/s then it returns with the same velocity.

So its kinetic energy=

2

1

mv

2

=

2

1

×2×(2)

2

=4J