from the top of our school building a boy drops marble.It falls on a heap of sand and comes to rest after travelling a distance of 135 CM in 0.15 seconds.Find the velocity of marble at the time of striking the sand heap
Answers
Explanation:
Assumption: the effect of air friction is negligible.
The acceleration of gravity on earth is 9.81m/s2.
To reach the ground in 3.5s from stationary, the velocity when it strike the ground, v can be calculated as:
(V-0)/3.5 = 9.81
V = 34.3m/s
The kinetic energy when it strike the ground is converted from its potential energy, therefore:
0.5mv2 = mgh
h = 0.5v2/g = (0.5 x 34.4^2)/9.81 = 60m
It is drop from a 60m high building.
Answer:
60m
Explanation:
Assumption: the effect of air friction is negligible.
The acceleration of gravity on earth is 9.81m/s2.
To reach the ground in 3.5s from stationary, the velocity when it strike the ground, v can be calculated as:
(V-0)/3.5 = 9.81
V = 34.3m/s
The kinetic energy when it strike the ground is converted from its potential energy, therefore:
0.5mv2 = mgh
h = 0.5v2/g = (0.5 x 34.4^2)/9.81 = 60m