W 20.
An iron block of mass 10 kg rests on a wooden plane inclined at 30°
to the horizontal. It is found that the least force parallel to the plane
which causes the block to slide up is 100 N. Calculate the coefficient
of friction between the two surfaces.
|NEB 2076]​

The great sandini is a 60.0-kg circus performer who is shot from a cannon (actually a spring gun). you don’t find many men of his caliber, so you him design a new gun. this new gun has a very large spring with a very small mass and a force constant of 1100 n/m that he will compress with a force of 4400 n. the inside of the gun barrel is coated with teflon, so the average friction force will be only 40.0 n during the 4.00 m he moves in the barrel. at what speed will he emerge from the end of the barrel, 2.50 m above his initial rest position?