A 3.5 kg block is pushed along a horizontal floor by a force of magnitude 15 N at an angle è = 40° with the horizontal. The coefficient of kinetic friction between the block and the floor is 0.25. Calculate the magnitudes of (a) the frictional force on the block from the floor and (b) the block's acceleration.

Question

A 3.5 kg block is pushed along a horizontal floor by a force  of magnitude 15 N at an angle è = 40° with the horizontal. The coefficient of kinetic friction between the block and the floor is 0.25. Calculate the magnitudes of (a) the frictional force on the block from the floor and (b) the block's acceleration.

Don · Accepted Answer

Thanks for the help guys, i have finally figured out this question after 8 years. I think I will pass my physics class this time around.

Can · Answer

(a) Friction= u * Normal Friction= 0.25 * Normal Normal=15*sin(40) + mg = 43.94 Friction= 0.25 * 43.94 = 10.985N (b) 19*cos(40) - 10.985 = 0.5 N F =ma 0.5N = 3.5kg * a a = 0.14 m/s^2

Rexix Media · Answer

correction on the above answer. It should say 15*cos(40) for part B.

John · Answer

This honestly is the best thing I've gotten out of physics so far. Made my day. Thank you Don.