Answer:
The rock's speed after 5 seconds is 98 m/s.
Explanation:
A rock is dropped off a cliff.
It had an initial velocity of 0 m/s. And now it is moving downwards under the influence of gravitational force with the gravitational acceleration of 9.8 m/s².
Speed after 5 seconds = V
We know that acceleration = average speed/time
In our case,
g = ((0+V)/2)/5
9.8*5 = V/2
=> V = 2*9.8*5
V = 98 m/s
Answer:
50 m/s
Explanation:
u = 0 m/s, t = 5 seconds, v = ? , g = 10 m/s^2
Use first equation of motion
v = u + g t
v = 0 + 10 x 5 = 50 m/s
