# Math Help - Physics, Newton question

1. ## Physics, Newton question

A dockworker applies a constant horizontal force of 80.0 N to a block of ice on a smooth horizontal floor. The frictional force is negligible. The block starts from rest and moves a distance 11.0 m in a time 4.50 s.

What is the mass of the block of ice?

If the worker stops pushing at the end of 4.50 s, how far does the block move in the next 5.90 s?
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I got the first part, 73.6 kg, but I'm not sure how to get the second part.

2. Originally Posted by dataspot
A dockworker applies a constant horizontal force of 80.0 N to a block of ice on a smooth horizontal floor. The frictional force is negligible. The block starts from rest and moves a distance 11.0 m in a time 4.50 s.

What is the mass of the block of ice?

If the worker stops pushing at the end of 4.50 s, how far does the block move in the next 5.90 s?
--

I got the first part, 73.6 kg, but I'm not sure how to get the second part.
You first need to calculate the final velocity of the block at the end of 4.5 seconds (first stage of motion):

s = 11 m, u = 0 m/s, t = 4.5 s, v = ?

Acceleration is constant therefore substitute into s = (u + v)t/2 and solve for v.

Second stage of motion:

t = 5.9 s, u = the value of v from above, a = 0 m/s^2, s = ?

Substitute into s = ut + at^2/2 and solve for s.

3. It seems simple enough, but I still can't get the correct answer. :\

4. Originally Posted by dataspot
It seems simple enough, but I still can't get the correct answer. :\