A boy pushes a 500kg box along a floor with a force of 2000N. If the velocity of the box is uniform, the co-efficient of friction between the box and the fl...
A boy pushes a 500kg box along a floor with a force of 2000N. If the velocity of the box is uniform, the co-efficient of friction between the box and the floor is
Answer Details
The coefficient of friction is a measure of the amount of friction between two surfaces. It is represented by the symbol "μ" and is a dimensionless quantity. The coefficient of friction between two surfaces depends on the nature of the surfaces in contact and the force pressing them together.
In this problem, the boy is pushing the box with a force of 2000N. If the box is moving with a uniform velocity, then the force of friction acting on the box is equal and opposite to the pushing force applied by the boy.
We can calculate the force of friction using the formula:
frictional force = coefficient of friction x normal force
where the normal force is the force exerted by the floor on the box in a direction perpendicular to the floor.
Since the box is not moving up or down, the normal force is equal to the weight of the box. The weight of the box can be calculated using the formula:
weight = mass x gravity
where mass is the mass of the box and gravity is the acceleration due to gravity (9.8 m/s^2).
So, the weight of the box is:
weight = 500 kg x 9.8 m/s^2 = 4900 N
The force of friction is equal to the pushing force of 2000N, so we can set these two equal to each other and solve for the coefficient of friction:
frictional force = 2000N
coefficient of friction x normal force = 2000N
coefficient of friction x 4900N = 2000N
coefficient of friction = 2000N / 4900N = 0.408
So, the coefficient of friction between the box and the floor is approximately 0.4. Therefore, the correct answer is 0.4.