Question

In the figure, we must apply a force of magnitude 80.0 N to hold the block stationary at x = -3.0 cm. From that position, we then slowly move the block so that our force does +7.0 J of work on the spring–block system; the block is then again stationary. What are the block's positions? ((a) positive and (b) negative)

Answer 1

I think it is a) positive as:

Work done = force * distance

So distance = work done / force

= 7 / 80

= 0.0875m so 8.75 cm

Then: -3 + 8 = 5 so the position is X= +5cm