You are Here: Home >< Physics

# compression KE question watch

1. spring constant is 1220nm^-1.

a ball is shot upwards, weighing 25g.
when spring compressed by 36mm work done is 0.81j, and if epe converted into KE, speed of ball is 8.05 ms^-1.

Question asks for compression of spring needed for ball to leave spring w/twice the speed (16.1ms^-1).

using the KE equation, i found that the KE needed would be 0.81*4, which is 3.24J. However I don't know how you would substitute that back to find the compression needed
2. (Original post by Deathlotus)
spring constant is 1220nm^-1.

a ball is shot upwards, weighing 25g.
when spring compressed by 36mm work done is 0.81j, and if epe converted into KE, speed of ball is 8.05 ms^-1.

Question asks for compression of spring needed for ball to leave spring w/twice the speed (16.1ms^-1).

using the KE equation, i found that the KE needed would be 0.81*4, which is 3.24J. However I don't know how you would substitute that back to find the compression needed
samb1234
3. (Original post by thefatone)
samb1234
Double the compression. Energy stored in the spring is proportional to extension/compression squared, so for 4times the energy need 2 times the compression

TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Updated: May 2, 2016
Today on TSR

Will it ever be possible?

### University open days

1. University of Cambridge
Wed, 26 Sep '18
2. Norwich University of the Arts
Fri, 28 Sep '18
3. Edge Hill University
Faculty of Health and Social Care Undergraduate
Sat, 29 Sep '18
Poll

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE