Answer:
5.09 m/s
Explanation:
Use the height to find the time it takes to land:
y = y₀ + v₀ᵧ t + ½ gt²
0 = 8.0 m + (0 m/s) t + ½ (-9.8 m/s²) t²
t = 1.28 s
Now use the horizontal distance to find the initial velocity.
x = x₀ + v₀ₓ t + ½ at²
6.5 m = 0 m + v₀ (1.28 s) + ½ (0 m/s²) (1.28 s)²
v₀ = 5.09 m/s
The velocity is the integral of acceleration. If acceleration is 100 m/s^2 then velocity is:

So to know the velocity at any time, t, we just put t in seconds into this equation. To know at what time we get to a certain velocity, we set this equation equal to that velocity and solve for t:
31.3m/s
Explanation:
Given parameters:
Mass of rock = 40kg
Height of cliff = 50m
Unknown:
Speed of rock when it hits ground = ?
Solution:
We are going to use the appropriate motion equation to solve this problem
The rock is falling with the aid of gravitational force. The force is causing it to accelerate with an amount of velocity.
Using;
V² = U² + 2gH
V = unknown velocity
U = initial velocity = O
g = acceleration due to gravity = 9.8m/s²
H = height of fall
since the initial velocity of the bodyg is 0
V² = 2gH
V= √2gH = √2 x 9.8 x 50 = 31.3m/s
learn more:
Velocity brainly.com/question/4460262
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