A ball is projected horizontally from the top of a vertical cliff 40m high at a velocity of 20ms-¹
1) time taken to get to the ground
2) the vertical component of the velocity on getting to the ground.
1) To find the time taken to get to the ground, we can use the equation:
h = 0.5 * g * t^2
where h is the height of the cliff (40m), g is the acceleration due to gravity (9.81m/s^2), and t is the time taken.
Plugging in the values:
40 = 0.5 * 9.81 * t^2
t^2 = 40 / (0.5 * 9.81)
t^2 = 8.15
t = √8.15
t ≈ 2.86 seconds
2) The vertical component of the velocity on getting to the ground can be found using the equation:
v = g * t
where v is the vertical component of the velocity and t is the time taken (2.86 seconds).
Plugging in the values:
v = 9.81 * 2.86
v ≈ 27.98 m/s
Therefore, the time taken to get to the ground is approximately 2.86 seconds and the vertical component of the velocity on getting to the ground is approximately 27.98 m/s.