Answer:
I think the answer is C too
The work done when a spring is stretched from 0 to 40cm is 4J.
What is work done?
Work done is the magnitude of force multiplied by displacement of an object. It is also the amount of energy transferred to an object when work is done on that.
The work done on the spring to stretch to 40cm is,
F = kx
where F is force, k is force constant.
k = F / x = 10 N / 20 * 10^-2 m = 50 N/m
W = 0.5 * k * (x)^2
where W = work done, k = force constant.
W = 0.5 x 50 x (40 x 10^-2)^2 = 4 J.
Therefore, the work done on the spring when it is stretched to 40cm is 4J.
To learn more about work done click on the given link brainly.com/question/25573309
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Answer:
-730KJ
Explanation:
According to the first law of thermodynamics;
Let the total energy of the system be ∆E
Let heat be q and let work the w
Since the energy decreases ∆E is negative
Since work is done on the system w= positive
So;
- 250 = 480 + q
q = -250 - 480
q=-730KJ
<span>❅☃ Lever
A winding mountain road is a example of a lever.</span>