A dog sled weighing 750 lb is pulled over level snow at a uniform speed by a dog team exerting a force of 60 lb. Find the coefficient of friction.
To find the coefficient of friction, we first need to understand the concept of friction. Friction is a force that opposes the motion between two surfaces in contact. It depends on the nature of the surfaces and the force applied between them.
In this scenario, the dog sled is being pulled over level snow with a force of 60 lb. The weight of the sled is 750 lb. We need to find the coefficient of friction between the sled and the snow.
Step 1: Calculate the force of gravity acting on the sled:
The weight of the sled is the force due to gravity acting on it. Weight is calculated as mass times acceleration due to gravity (W = mg). In this case, the sled's weight would be 750 lb.
Step 2: Calculate the frictional force:
The force of friction can be calculated by multiplying the coefficient of friction by the normal force. In this case, the normal force would be equal to the weight of the sled (750 lb).
Frictional force = coefficient of friction * normal force
Step 3: Calculate the coefficient of friction:
To find the coefficient of friction, we can rearrange the equation for the frictional force:
coefficient of friction = frictional force / normal force
In this case, the frictional force is equal to the force exerted by the dogs (60 lb).
coefficient of friction = 60 lb / 750 lb
The friction force Ff = 60 lb equals the pulling force, since it is not accelerating.
The coefficient of kinetic friction is
(pulling force)/(weight) = 60lb/750lb
= 0.080 (a dimensionless number)