Answer:
23.52 m/s
Explanation:
The following data were obtained from the question:
Time taken (t) to reach the maximum height = 2.4 s
Acceleration due to gravity (g) = 9.8 m/s²
Initial velocity (u) =..?
At the maximum height, the final velocity (v) is zero. Thus, we can obtain how fast the rock (i.e initial velocity)
was thrown as follow:
v = u – gt (since the rock is going against gravity)
0 = u – (9.8 × 2.4)
0 = u – 23.52
Collect like terms
0 + 23.52 = u
u = 23.52 m/s
Therefore, the rock was thrown at a velocity of 23.52 m/s.
Gravitational potential energy = mass x acceleration due to gravity x height
GPE=mgh
4620=mx9.81x8.4
4620/(9.81x8.4)=m=56.1 kg
A/c/d. that is the anser hope it helps
Explanation:
When bullet is shot towards the monkey then let say the distance of monkey from the bullet is "d"
so we can find the time to reach the bullet to the monkey

Now similarly we can find the vertical displacement of the bullet in the same time


so it is given as

here if the monkey is initially at height H above the ground at given angle then we can say

so we can say that

So if at the same time monkey will fall down then the height of monkey from ground after time "t" is given as

so here bullet will hit the monkey as both monkey and bullet are at same position.