A force of 20N applied parallel to the surface of a horizontal table is just sufficient to make a block 4kg move on a table, calculate coefficient of friction between the block and the table.
mu m g = 20 N
mu (4)g = 20
mu = 5/g so about 0.5
Raymond
To calculate the coefficient of friction between the block and the table, we need to use the formula:
Coefficient of friction (μ) = Force of friction (Ff) / Normal force (Fn)
Step 1: Determine the normal force acting on the block.
The normal force (Fn) is equal to the weight of the block. The weight of the block can be calculated using the formula:
Weight = Mass × gravitational acceleration
Given that the mass of the block is 4 kg, and the gravitational acceleration is approximately 9.8 m/s^2, we can calculate the weight:
Weight = 4 kg × 9.8 m/s^2 = 39.2 N
Therefore, the normal force acting on the block is 39.2 N.
Step 2: Calculate the force of friction.
The force of friction (Ff) can be calculated using the formula:
Ff = μ × Fn
Given that the applied force is 20 N, and the block is moving with this applied force, we can conclude that the force of friction is equal to the applied force. Therefore, Ff = 20 N.
Step 3: Calculate the coefficient of friction.
Using the formula for the coefficient of friction:
μ = Ff / Fn
We can substitute the values:
μ = 20 N / 39.2 N
Calculating this division gives us:
μ ≈ 0.51
Therefore, the coefficient of friction between the block and the table is approximately 0.51.
To calculate the coefficient of friction between the block and the table, we need to use the given force applied and the weight of the block.
1. First, we need to determine the weight of the block, which is given by the formula:
Weight = mass × gravitational acceleration
In this case, the mass of the block is 4 kg.
The gravitational acceleration is approximately 9.8 m/s^2.
Therefore, the weight of the block is: Weight = 4 kg × 9.8 m/s^2 = 39.2 N
2. Since the applied force of 20 N is just sufficient to make the block move horizontally on the table, it means the force of friction opposing the motion is equal in magnitude to the applied force.
3. The force of friction is given by the equation:
Force of friction = coefficient of friction × normal force
Since the block is on a horizontal table, the normal force (force perpendicular to the surface) is equal to the weight of the block.
Therefore, the normal force in this case is 39.2 N.
4. From step 2, we know that the force of friction equals the applied force, so we have:
Force of friction = 20 N
5. Substituting the known values into the equation from step 3, we have:
20 N = coefficient of friction × 39.2 N
6. Solving for the coefficient of friction:
coefficient of friction = 20 N ÷ 39.2 N ≈ 0.51
Therefore, the coefficient of friction between the block and the table is approximately 0.51.