A force of 12 N acts on an object of mass 10kg and moves it with a constant velocity across a floor. What is the coefficient of fiction between the object and the floor?
Since the object is not accelerating, the net force is zero and the friction force is 12N (backwards).
The (kinetic) friction force is therefore
mu = 12N/(M*g) = 12/98 = 0.1224
To find the coefficient of friction between the object and the floor, we can use the concept of frictional force.
The first step is to determine the gravitational force acting on the object. The gravitational force is given by the equation:
Gravitational force (Fg) = mass (m) × acceleration due to gravity (g)
In this case, the mass of the object is 10 kg, and the acceleration due to gravity is approximately 9.8 m/s². Therefore, the gravitational force is:
Fg = 10 kg × 9.8 m/s² = 98 N
Since the object is moving with a constant velocity across the floor, it means that the force of friction opposing the object's motion is equal in magnitude and opposite in direction to the applied force of 12 N.
Therefore, the force of friction (Ff) is 12 N.
The force of friction can be calculated using the equation:
Ff = coefficient of friction (μ) × normal force (Fn)
The normal force (Fn) is the force experienced by the object due to its weight and is equal in magnitude and opposite in direction to the gravitational force acting on the object. Therefore, the normal force is:
Fn = Fg = 98 N
Now, we can substitute the values into the equation to find the coefficient of friction:
12 N = μ × 98 N
To isolate the coefficient of friction (μ), divide both sides of the equation by 98 N:
μ = 12 N / 98 N ≈ 0.122
Therefore, the coefficient of friction between the object and the floor is approximately 0.122.