Bobby and Ricky are using a ramp to load furniture into a tr

Bobby and Ricky are using a ramp to load furniture into a truck. While rolling a 250-pound piano up the ramp, they discover that the truck is too full with other furniture for the piano to fit. Ricky holds the piano in place on the ramp while Bobby repositions other items to make room for it in the truck. If the angle of inclination of the ramp is 15degree how many pounds of force must Ricky exert to hold the piano in position?

Solution

the minimum force to hold the piano = mgsin15 = 250 x g x sin15 lb = 64.70476g lb = 64.70476 lbf = 64.70476 pound of force.