Question

A body of mass 5 kg is dropped from a height of 20m above the ground. Calculate its potential energy and kinetic energy at Midway during falling.

Answer 1

Solution

mass(m)=5kg

height (h)=20m

at the midway... height (h1) from the ground or from the top is =10m

potential energy(p.E.)=mg(h1)=(5×9.8×10)J

=490 Joule

now.....

distance (h1)=10m

initial velocity (u)=0

velocity at the midway= v (final velocity)

v²=u²+2g(h1)

=>v²=2g(h1)=2(9.8)(10)

=>v=√(98×2)=14

=>v=14 m/s

therefore... kinetic energy (K.E.)at midway is

$= \frac{1}{2} mv {}^{2} \\ = (\frac{1}{2} \times 5 \times 14 {}^{2}) \: joule \\ = 490 \: joule$

$\:\:\:\: \large\mathfrak{\underline{\huge\mathcal{\bf{\boxed{\boxed{\large\mathcal{P.E.=K.E.=490 Joule}}}}}}}$

N.B.

i.e., at the midway of journey of the body K.E. &P.E. both are same

Answer 2

Answer:

Total energy of a mass m moving with speed v and at a height h above ..... Part of that energy went into the kinetic energy of your car.