A block is sliding down a frictionless incline. If the incline is now covered wi
Practice Questions
Q1
A block is sliding down a frictionless incline. If the incline is now covered with a material that has a coefficient of kinetic friction of 0.3, how does this affect the acceleration of the block?
Increases acceleration
Decreases acceleration
No effect on acceleration
Acceleration becomes zero
Questions & Step-by-Step Solutions
A block is sliding down a frictionless incline. If the incline is now covered with a material that has a coefficient of kinetic friction of 0.3, how does this affect the acceleration of the block?
Correct Answer: Acceleration will decrease due to friction.
Step 1: Understand that a block sliding down an incline experiences gravity pulling it downwards.
Step 2: Know that on a frictionless incline, the only force acting on the block is gravity, which causes it to accelerate down the slope.
Step 3: Introduce the concept of kinetic friction, which is a force that opposes the motion of the block.
Step 4: Recognize that the coefficient of kinetic friction (0.3) indicates how much frictional force will act against the block's motion.
Step 5: Calculate the frictional force using the formula: Frictional Force = Coefficient of Kinetic Friction × Normal Force.
Step 6: Understand that the normal force on an incline is less than the weight of the block and is calculated as: Normal Force = Weight × cos(θ), where θ is the angle of the incline.
Step 7: Realize that the net force acting on the block is now the gravitational force down the incline minus the frictional force.
Step 8: Conclude that the presence of kinetic friction reduces the net force acting on the block, which in turn decreases its acceleration compared to when the incline was frictionless.
Inclined Plane Dynamics – Understanding the forces acting on an object sliding down an incline, including gravitational force and friction.
Friction – The role of kinetic friction in opposing motion and its effect on acceleration.
Newton's Second Law – Application of F=ma to determine the net force and resulting acceleration of the block.
