Work Done on 12kg Mass: 52N - 15N over 24m

[dance_sg]

Homework Statement

A force of 52 N is applied to a 12 kg mass resting on a bench where the force of sliding friction is 15 N. The work done in overcoming friction while moving the object 24 m is

Homework Equations

w=fd

The Attempt at a Solution

could i just subtract 15N from 52N, then multiply that number by 24m to find the work??

 

[ideasrule]

Why subtract? 52-15 would be the net force on the object, so if you plug that into W=Fd, you'd find the block's final kinetic energy. You want the work done by friction--which, because of the conservation of energy, is equal to the work done in overcoming friction.

 

[rl.bhat]

Homework Statement

A force of 52 N is applied to a 12 kg mass resting on a bench where the force of sliding friction is 15 N. The work done in overcoming friction while moving the object 24 m is

Homework Equations

w=fd

The Attempt at a Solution

could i just subtract 15N from 52N, then multiply that number by 24m to find the work??

The work done in overcoming friction = frictional force X displacement.

 

[dance_sg]

so all i do is multiply 15N by 24m??

 

[ideasrule]

Yes, that's the work done by friction.