Posted by **Shelly** on Monday, December 3, 2012 at 6:34pm.

An automobile of mass 2000 kg is driven into a brick wall in a safety test. The bumper behaves like a Hooke’s-law spring. It has an effective spring constant of 5 × 106 N/m, and is observed to compress a distance of 8.7 cm as the car is brought to rest. What was the initial speed of the automobile?

Answer in units of m/s

i used PE=(.5)(k)(d^2)

so

PE=.(.5)(5x10^6)(.087^2) =18922.5

then from there im not sure what do to, did i do that part and where do i go from there?

thanks

## Answer This Question

## Related Questions

- Physics - An automobile having a mass of 1220 kg is driven into a brick wall in ...
- physics - An automobile having a mass of 1330 kg is driven into a brick wall in ...
- Physics - A 2 kg brick falls at 5.1 m/s from a height of 6 m above a spring that...
- Physics - A 2 kg brick falls at 5.1 m/s from a height of 6 m above a spring that...
- urgent (physics) - A 2 kg brick falls at 5.1 m/s from a height of 6 m above a ...
- Physics - A 3 kg block collides with a massless spring of spring constant 90 N/m...
- Physics - A 3.0 kg brick rests on a perfectly smooth ramp inclined at 34 above ...
- Physics - A 3.0 kg brick rests on a perfectly smooth ramp inclined at 34 above ...
- Physics - A 3.0 kg brick rests on a perfectly smooth ramp inclined at 34 above ...
- Physics - A 3.0-kg brick rests on a perfectly smooth ramp inclined at 34° above ...

More Related Questions