A child pulls a wagon at a constant velocity of 4.0 m/s for 4.0 minutes along a level sidewalk. The child does this applying a 22 N force to the wagon handle, which is inclined at 35 ° to the sidewalk as shown below. How much work does the child do on the wagon ? 288 k J
8.7 kJ
17.3 kJ
2.3 kJ

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?