Question

The force applied against an object moving horizontally on a linear path is described by `F(x)= 4x^2+5x`. By how much does the object's kinetic energy change as the object moves from `x in [ 1, 2 ]`?

Answer 1

`35/3`unit

Explanation:

Kinetic energy gained by the object is equlal to the work done by the aplied foce .So KE= `int_1^2F(x)dx=int_1^2(4x^2+5x)dx`
`=[4x^3/3+5x^2/2]_1^2=4*2^3/3+5*2^2/2-4*1^3/1-5*1^2/1=35/3`