Answer:
The friction force that exerts by the floor on the box is 10 N.
Explanation:
Given that,
Weight of the box, W = 50 N
The coefficient of static friction is 0.2
A rope is attached to the box and pulled horizontally to the right. We need to find the friction force that exerts by the floor on the box. The direction of frictional force is in left side as we know that the frictional force acts in the opposite direction of motion. The force of friction is given by :
N is normal reaction, N = W = 50 N
So, the friction force that exerts by the floor on the box is 10 N.
Answer:
Explanation:The main purpose of astronomical telescope is to make objects from outer space appear as bright, contrasty and large as possible. That defines its three main function: light gathering, resolution and magnification. These are the measure of its efficiency.
(a) For the work-energy theorem, the work done to lift the can of paint is equal to the gravitational potential energy gained by it, therefore it is equal to
where m=3.4 kg is the mass of the can, g=9.81 m/s^2 is the gravitational acceleration and 
is the variation of height. Substituting the numbers into the formula, we find
(b) In this case, the work done is zero. In fact, we know from its definition that the work done on an object is equal to the product between the force applied F and the displacement:
However, in this case there is no displacement, so d=0 and W=0, therefore the work done to hold the can stationary is zero.
(c) In this case, the work done is negative, because the work to lower the can back to the ground is done by the force of gravity, which pushes downward. Its value is given by the same formula used in part (a):
Answer:
An asteroid moving at a constant speed through space.
Explanation:
I believe the correct answer from the choices listed above is the third option. <span>The force exerted by the book on the table is equal to the force exerted by the table which is 4.0 N. The book does not move so it must be that the forces are balanced. Hope this answers the question.</span>
