Saturday

October 25, 2014

October 25, 2014

Posted by **Mario** on Thursday, October 1, 2009 at 11:32am.

(a) What is the coefficient of static friction?

(b) What is the coefficient of kinetic friction?

- Physics -
**drwls**, Thursday, October 1, 2009 at 12:03pm(a) Let s be the coefficient of statice froction and k be the coefficient of kinetic friction.

From the info on the angle at whic slidign starts,

M g sin 30 = M g s cos 30

tan 30 = s

(b) Solve for the acceleration rate a after sliding begins. It slides a distance X in time T.

a T^2/2 = X

a = 2X/T^2

Then solve for k using Newton's second law.

M a = Mg sin 30 - M g k cos 30

a/g = sin 30 - k cos 30

**Answer this Question**

**Related Questions**

PHYSICS - A student wants to determine the coefficients of static friction and ...

physics - A student wants to determine the coefficients of static friction and ...

physics - A 2.0kg box rests on a plank that is inclined at an angle of 65° above...

spring- physics - A 2.0-kg box rests on a plank that is inclined at an angle of ...

Spring Physics - A 2.0 kg box rests on a plank that is inclined at an angle of ...

Physics - A m = 1.85 kg box rests on a plank that is inclined at an angle of &#...

Physics 204 - If there is a 23lb. block on a plank and the static friction is .6...

Physics - A wooden plank is inclined at and angle of 23 degrees above the ...

physics - A 5-kg crate is resting on a horizontal plank. The coeï¬ƒ- cient of ...

physics - a 5-kg crate is resting on a horizontal plank. the coefficient of ...