Suvat and Friction on a slope

Question 1

What is the equation for the frictional force?

Answer 1

Ff=μFn

The force of friction is equal to the coefficient of friction multiplied by the normal force

Question 2

A 20t truck is stationary on a 20 degree slope, but is on the verge of slipping down. In which direction will the force of friction be?

Answer 2

Up the slope

Question 3

A 30t truck is stationary on a 40 degree slope, and is supported by a rope that is on the verge of pulling it up. In which direction will the force of friction be?

Answer 3

Down the slope

Question 4

Find the angle of repose of a 5t car if the coefficient of friction between the car and the slope if 0.4.

Answer 4

21.8deg

Question 5

A toy car is placed on a ramp set an angle of 5o. The car has a mass of 2Kg. The frictional coefficient between the wheels and the ramp is 0.3. Calculate the force required to begin pushing the toy car up the ramp..

Answer 5

7.57N

Question 6

A motorbike has a passenger on the back and is going up a 15o hill. The coefficient of static friction between the passenger and the seat is 0.45. Find the maximum acceleration that the bike can attain before the passenger begins to slip backward.

Answer 6

1.72m/s/s