November 5November 5 physicsphysics

In: A 3 kg book slides In: A 3 kg book slides across a table and across a table and decelerates to a decelerates to a stop. The stop. The acceleration is -5 acceleration is -5 m/sm/s22..

What is the force of What is the force of friction on the table?friction on the table?

What is the What is the µ of the µ of the table/book table/book combination?combination?

Objective:Objective:To Show our understanding To Show our understanding

of the force of friction by of the force of friction by taking a quiz.taking a quiz.

Success criteria:Success criteria:To be able to solve friction To be able to solve friction

equations using Ff Fn and equations using Ff Fn and μμ

Ignoring the slippery Ignoring the slippery when wet sign, a 150 when wet sign, a 150 kg man steps kg man steps carelessly. What is carelessly. What is the coefficient of the coefficient of friction if the force of friction if the force of friction was 25 N?friction was 25 N?

A glacier has a mass A glacier has a mass

of 5x10of 5x1010 10 kg and kg and

moves at a constantmoves at a constant

velocity of .5 m/day.velocity of .5 m/day.

If the force of friction between glacier If the force of friction between glacier and rock is .2, what is the force of and rock is .2, what is the force of friction scraping the rock below the friction scraping the rock below the glacier?glacier?

Slip tech is a product that treats Slip tech is a product that treats surfaces to make them less slippery. If surfaces to make them less slippery. If a 200 kg man stepped on each of a 200 kg man stepped on each of these materials, how much more force these materials, how much more force of friction would he have with this of friction would he have with this product?product?

A 20 N block is being pushed across a A 20 N block is being pushed across a horizontal table by an 18 N force. If horizontal table by an 18 N force. If the coefficient of kinetic friction the coefficient of kinetic friction between the block and the table is between the block and the table is 0.4, find the acceleration of the 0.4, find the acceleration of the block.block.

a) 0.5 m/sa) 0.5 m/s22

b) 1 m/sb) 1 m/s22

c) 5 m/sc) 5 m/s22

d) 7.5 m/sd) 7.5 m/s22

e) 9 m/se) 9 m/s22

Problem creationProblem creation

QuizQuiz

Out:Out:

What still What still confuses confuses you about you about friction?friction?