Depending on what you are working with, it would be a solid
Answer:
Explanation:
Given that,
Height of the bridge is 20m
Initial before he throws the rock
The height is hi = 20 m
Then, final height hitting the water
hf = 0 m
Initial speed the rock is throw
Vi = 15m/s
The final speed at which the rock hits the water
Vf = 24.8 m/s
Using conservation of energy given by the question hint
Ki + Ui = Kf + Uf
Where
Ki is initial kinetic energy
Ui is initial potential energy
Kf is final kinetic energy
Uf is final potential energy
Then,
Ki + Ui = Kf + Uf
Where
Ei = Ki + Ui
Where Ei is initial energy
Ei = ½mVi² + m•g•hi
Ei = ½m × 15² + m × 9.8 × 20
Ei = 112.5m + 196m
Ei = 308.5m J
Now,
Ef = Kf + Uf
Ef = ½mVf² + m•g•hf
Ef = ½m × 24.8² + m × 9.8 × 0
Ef = 307.52m + 0
Ef = 307.52m J
Since Ef ≈ Ei, then the rock thrown from the tip of a bridge is independent of the direction of throw
Answer:
17.6 m/s²
Explanation:
Given:
= 90 m/s (final velocity)
= 2 m/s (initial velocity)
Δt = 5s (change in time)
The formula for acceleration is:
= Δv / Δt
We can find Δv by doing
Δv = -
Replace the values
Δv = 90m/s - 2m/s
Δv= 88m/s
Using the equation from earlier, we can find the acceleration by dividing the average velocity by time.
= Δv / Δt
= 
acceleration = 17.6 
