To solve this, we use Newtons 2nd law of motion which states that F = m⋅a . This means that a force F is required to make a body of mass m accelerate with an acceleration of a . So if a body of 4kg is to be accelerated by a force 17N then its acceleration can be found by putting into the formula F = m⋅a .
<span>They are balanced. If the forces were not balanced the book would move*. In this example, the downward force of gravity on the book is counterbalanced by the upthrust of the desk. </span>
Reducing Sliding Friction. You can reduce the resistive force of sliding friction by applying lubrication between the two surfaces in contact, by using rollers, or by decreasing the normal force