Question

i) A spring ball of mass 0.5 kg is dropped
from some height. On falling freely for
10 s, it explodes into two fragments of
mass ratio 1:2. The lighter fragment
continues to travel downwards with
speed of 60 m/s. Calculate the kinetic
energy supplied during explosion.
[Ans: 200 J]
xvi)​

Answer 1

Answer:

200 J

Explanation:

After the spring mass system is released from rest the system will fall down under gravity

So after t = 10 s the speed of the spring mass system is given as

$v = v_i+at\\v = 0 +10(10)\\v = 100m/s$

Now we know by momentum conservation:

$Mv_1=m_1v_1f+m_2v_2f$

here we have:

$M(100) = \frac{M}{3} *60+\frac{2M}{3} *v_2f\\100 = 20 + \frac{2}{3} v_2f\\v_2f = 120~m/s$

now kinetic energy supplied by the explosion is given as:

$K = \frac{1}{2}* \frac{0.5}{3}*60^2+ \frac{1}{2}* \frac{1}{3}*120^2- \frac{1}{2} *0.5^2*100^2$

Therefore

KE = 200 J

Mark as brainliest if you are satisfied with my answer.