# physics - Energy

posted by .

An ore car of mass 41000 kg starts from rest and rolls downhill on tracks from a mine. At the end of the tracks, 9.6 m lower vertically, is a horizontally situated spring with constant 4.7 × 10^
5 N/m.
The acceleration of gravity is 9.8 m/s^
2. Ignore friction.
How much is the spring compressed in stopping the ore car? Answer in units of m.

• physics - Energy -

Gravitational potential energy loss = Spring potential energy increase

M g H = (1/2) k X^2

k = 4.7*10^5 N/m
M = 4.1*10^4 kg
H = 9.6 m
You known what g is.

Solve for X

• physics - Energy -

Thank you!

• physics - Energy -

I got it wrong. I did exactly what you said. Multiplied m times g times h then multiplied by 2. Sq root that number and got 2778.926411 but it was wrong.

• physics - Energy -

X = sqrt(2 M g H/k)
= 4.54 m

You forgot to divide by k, the spring constant.

## Similar Questions

1. ### PHYSICS HELPPPP

A loaded ore car has a mass of 880 kg and rolls on rails with negligible friction. It starts from rest and is pulled up a mine shaft by a cable connected to a winch. The shaft is inclined at 28.0° above the horizontal. The car accelerates …
2. ### physics

A loaded ore car has a mass of 935 kg and rolls on rails with negligible friction. It starts from rest and is pulled up a mine shaft by a cable connected to a winch. The shaft is inclined at 26.0° above the horizontal. The car accelerates …
3. ### physics

An ore car of mass 42000 kg starts from rest and rolls downhill on tracks from a mine. At the end of the tracks, 6.8 m lower vertically, is a horizontally situated spring with constant 3.8 x 10^5 N/m. The acceleration of gravity is …
4. ### physics

An ore car of mass 37000 kg starts from rest and rolls downhill on tracks from a mine. At the end of the tracks, 28 m lower vertically, is a horizontally situated spring with constant 2.8 × 10 5 N/m. The acceleration of gravity is …
5. ### Physics

An ore car of mass 37000 kg starts from rest and rolls downhill on tracks from a mine. At the end of the tracks, 9.9 m lower vertically, is a horizontally situated spring with constant 3.9 × 10 5 N/m. The acceleration of gravity is …
6. ### physics

An ore car of mass 36000 kg starts from rest and rolls downhill on tracks from a mine. At the end of the tracks, 21 m lower vertically, is a horizontally situated spring with constant5.1×10^5N/m.The acceleration of gravity is 9.8 …
7. ### physics

An ore car of mass 40000 kg starts from rest and rolls downhill on tracks from a mine. At the end of the tracks, 16 m lower vertically, is a horizontally situated spring with constant 2.7 × 105 N/m. The acceleration of gravity is …
8. ### Physics

A steel spring is hung vertically. Using a ruler, the lower end of the spring was measured to be 25.0cm from its upper end. However, when an object of mass 0.500kg it attracted to the lower end of the spring the spring stretches to …
9. ### Physics

An ore car of mass 44000 kg starts from rest and rolls downhill on tracks from a mine. At the end of the tracks, 26 m lower vertically, is a horizontally situated spring with constant 4.5 × 105 N/m. The acceleration of gravity is …
10. ### physics

An ore car of mass 41000 kg starts from rest and rolls downhill on tracks from a mine. At the end of the tracks, 29 m lower vertically, is a horizontally situated spring with constant 4.1 × 105 N/m. The acceleration of gravity is …

More Similar Questions