Understanding Friction: Concepts and Calculations

What is the primary role of friction in motion?

• To assist motion

• To increase speed

• To decrease mass

• To oppose motion

Which type of friction occurs when an object is not moving?

• Kinetic friction

• Static friction

• Dynamic friction

• Rolling friction

What happens to the force required to move an object once it starts moving?

• It increases

• It becomes zero

• It decreases

• It remains the same

What is the relationship between static and dynamic friction?

• Static friction is always less than dynamic friction

• Static friction is always greater than dynamic friction

• Static friction is equal to dynamic friction

• Static friction does not exist

What is the coefficient of friction?

• A type of friction

• A measure of mass

• A unitless multiplier

• A force

How is the normal reaction force related to friction?

• It opposes friction

• It is used to calculate friction

• It is the same as friction

• It is unrelated

What must be known to calculate the force of friction?

• Only the mass

• Only the normal force

• Only the coefficient of friction

• Both the normal force and the coefficient of friction

In the example problem, what is the mass of Santa's sleigh?

• 1500 kg

• 2500 kg

• 2000 kg

• 1000 kg

What is the value of gravitational acceleration used in the calculations?

• 11.81 m/s²

• 8.81 m/s²

• 9.81 m/s²

• 10.81 m/s²

What is the acceleration of the sleigh when the reindeer pull with 4980 N?

• 4 m/s²

• 3 m/s²

• 2 m/s²

• 1 m/s²