An object with a mass of #2 kg# is on a surface with a kinetic friction coefficient of # 9 #. How much force is necessary to accelerate the object horizontally at #6# #ms^-2#?
If the object were on a frictionless surface the force required would be
This is a very badly written question: the friction coefficient should have values between 0 and 1. Very rarely it can have values greater than one, and perhaps as high as 2, but 9 is a ridiculous and non-physical number. Are you sure it wasn't 0.9 and you missed something when writing down the question?
First we can calculate the required force due to the object's inertia:
This is the force we'd need on a frictionless surface.
To calculate the frictional force, use:
To find the total force required we would add this to the