Answer:
W = 100000 J = 100 KJ
Explanation:
Here we will use the most basic and general formula of work, which is as follows:

where,
W = Work Done = ?
F = Force Required = 200 N
d = Length of Track = 500 m
Therefore,

<u>W = 100000 J = 100 KJ</u>
Answer:
A
Explanation:
Hooke's law! F(spring)=-kx
There's no tricky square law here. The spring constant doesn't change, only x (distance stretched) changes. Therefore, if distance is halved, Force will be halved.
Take 320 and divide by 8
320/8 = 40 mi/hr or A