A box weighing 87 lb is being pulled with a rope that exerts a force of 60. lb at an angle of 15 degrees with the horizontal. if the coefficient of kinetic friction is .35, what is the kinetic friction?

the rope being at an angle reduces the effective weight for the friction calculation

{87 - [60 sin(15º)]} * .35

To find the kinetic friction, we need to use the formula:

kinetic friction = coefficient of kinetic friction * normal force

Initially, we need to calculate the normal force, which is the force exerted by a surface that is perpendicular to the weight of the object.

1. First, find the vertical component of the force being exerted by the rope:

vertical force = force * sin(angle)
= 60 lb * sin(15 degrees)

2. Then, subtract the vertical force from the weight of the box to get the normal force:

normal force = weight - vertical force
= 87 lb - (60 lb * sin(15 degrees))

3. Finally, calculate the kinetic friction using the equation:

kinetic friction = coefficient of kinetic friction * normal force
= 0.35 * normal force

Plug in the value of the normal force calculated in step 2 to get the answer.