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View Full Version : Physics Kinetic energy help


ryan200666
Oct 7, 2013, 06:28 AM
A father racing his son has half the kinetic energy of the son, who has one-third the mass of the father. The father speeds up by 1.0 m/s and then has the same kinetic energy as the son.

(a) What is the original speed of the father?

(b) What is the original speed of the son?

Can anyone help me with this? I got a mess of equations. I got 2.96 for answer a, but it was wrong

ebaines
Oct 7, 2013, 07:19 AM
Here's a hint: use the fact that increasing the father's velocity by 1 m/s doubles his KE (to make it the same as the son's) - from this you can deterimine his velocity. What do you get?

ryan200666
Oct 7, 2013, 02:43 PM
I got the speed for the father which was 2.41, this one is correct. Now I have no idea what the sons is