Answer:
t = 5.1[s]
Explanation:
To solve this problem we must first use the following equation of kinematics.

where:
Vf = final velocity = 0
Vo = initial velocity = 25 [m/s]
g = gravity acceleration = 9.81 [m/s²]
t = time [s]
Now replacing:
![0 = 25-9.81*t\\t=25/9.81\\t=2.54[s]](https://tex.z-dn.net/?f=0%20%3D%2025-9.81%2At%5C%5Ct%3D25%2F9.81%5C%5Ct%3D2.54%5Bs%5D)
Note: The key to understand this problem is that when the tennis ball is in the highest position its velocity is zero.
So it will take the same time from the highest point to the ground
t = 2.54 +2.54
t = 5.09 [s]
Answer: option b, the distance the spring stretches.
Hook's law is: F = - K Δx
Where:
F stands for the force that the spring exerts
K is stands for the constant of the spring
Δx stands for the distance the spring is displaced from the equilibrium point.
And the negative sign is due to F is opposite to the direction in which the spring is away from the equilibrium point.
Answer:
This conversion of 1.5 days to minutes has been calculated by multiplying 1.5 days by 1,440 and the result is 2,160 minutes.
Explanation:
While moving box from car to house
<span>W = F * d * cosine (90 degree)
</span>= 10N * 200m * 0
= 0Nm
While lifing 3m tall flight of stairs
W=F*d*cosine(0 degree)
= 10N * 3m
= 300 Nm
George did more work