# An object with a mass of 2 kg is on a surface with a kinetic friction coefficient of  3 . How much force is necessary to accelerate the object horizontally at 6 m/s^2?

Mar 4, 2018

$70.8 N$

#### Explanation:

Here,if we have to move the object against frictional force with acceleration,then frictional force must be exerting its maximum value against the motion.

Maximum frictional $f$ force that can act here is $\mu N = \mu g = 3 \cdot 2 g = 6 \cdot 9.8 = 58.8 N$ (where, $\mu$ is the coefficient of kinetic friction)

So,if we need to apply force $F$ to accelerate it at an acceleration of $a$,

Then we can write,acceleartion which is due to the net force acting is,

$F - f = m a$

or, $F - 58.8 = 2 \cdot 6$

so, $F = 70.8 N$