A 5 kg object is at rest on a surface with a coefficient of static friction of 0
Practice Questions
Q1
A 5 kg object is at rest on a surface with a coefficient of static friction of 0.4. What is the maximum static friction force?
10 N
20 N
30 N
40 N
Questions & Step-by-Step Solutions
A 5 kg object is at rest on a surface with a coefficient of static friction of 0.4. What is the maximum static friction force?
Correct Answer: 20 N
Step 1: Identify the mass of the object. The mass is given as 5 kg.
Step 2: Identify the coefficient of static friction (μs). It is given as 0.4.
Step 3: Calculate the weight of the object (N). Use the formula: Weight = mass * gravity. Here, gravity is approximately 9.8 m/s².
Step 4: Calculate the weight: Weight = 5 kg * 9.8 m/s² = 49 N.
Step 5: Use the formula for maximum static friction force: Maximum static friction force = μs * N.
Step 6: Substitute the values into the formula: Maximum static friction force = 0.4 * 49 N.
Step 7: Calculate the maximum static friction force: 0.4 * 49 N = 19.6 N.
Step 8: Round the answer to the nearest whole number if needed: approximately 20 N.
Static Friction – The force that resists the initiation of sliding motion between two surfaces in contact, calculated as the product of the coefficient of static friction and the normal force.
Normal Force – The force exerted by a surface to support the weight of an object resting on it, equal to the object's weight when on a horizontal surface.
Coefficient of Static Friction – A dimensionless value that represents the ratio of the maximum static friction force to the normal force.
