An object of mass 5 kg is acted upon by a force that varies with position of the object as shown. If the object starts out from rest at a point x=0. What is its speed at x=50 m.

Options

A. `12.2 ms^(-1)`
B. `18.2 ms^(-1)`
C. `16.4 ms^(-1)`
D. `20.4 ms^(-1)`

Answer

A

Explanation

(a) Change in kinetic energy =work done
=Area under F-x graph
`:. (1)/(2)xx5xxv^(2)=10xx25+(1)/(2)xx25xx10=375`
`:. " " v=122 ms^(-1)`