Question

In physics lab, a force of 175.7 N is applied to a 7.2 kg cart to accelerate it across a horizontal surface at a rate of 5 m/s^2.

What is the net force acting on the cart? F net =___________ unit__________

What is the force of friction acting on the cart? F friction =____________ unit__________

Answer 1

According to the equation of motion
  
where, m is the mass of the cart, a is the acceleration of the cart and is the net force acting on the cart.
And net force is given by

where,
   is the applied force and is the frictional force and the relative negative sign between the two is because frictional force acts in the opposite direction to the applied force. And so,
putting the given values,

i)
we get the net force as

  
ii)
Frictional force is given by

so, putting the values, we get