Calculating Final Speed with Given Work

[markmil2002]

1. A 4.00 kg block is traveling 15.0 m/s. (a) How fast is the block traveling if 2.00 x 10^2 J of work is done on the block? (b) If -2.00 x 10^2 of work is done on the block instead, what would be the final speed?

Homework Equations

KE = 1/2mv^2

The Attempt at a Solution

a KE = 4.5 x 10^2 + 2.0 x 10^2
b 4.5 x 10^2 J - 2.0 X 10^2

 

[G01]

What is your question?

Also, the Advanced Physics forum is more for problems from upper level undergraduate (300-400 level) physics course. Please post problems like these in the Intro Physics Forum.

 

[markmil2002]

Well I got the question wrong with the work that I did, so I waned to know what I did wrong.