# How much work would it take to horizontally accelerate an object with a mass of #2"kg"# to #9"m/s"# on a surface with a kinetic friction coefficient of #3#?

##### 1 Answer

It can be anything greater than

#### Explanation:

From the Work-Energy Theorem, the work done equals to the change in kinetic energy of the object and the energy loss due to friction.

The **change in kinetic energy**,

It will be "81"J"# no matter how you push the object, so the work done will be at least that.

The **work done against friction** on the other hand, can vary from *infinitesimally small* to *infinitely big*. Let's consider the 2 extreme cases intuitively.

The fundamental reason is that the energy lost is the product of the

In the case where a huge force is applied, the objects reaches the final speed of

On the other end of the spectrum, consider applying a constant force of