1. A 170 g hockey puck sliding at 25 m/s slows to a speed of 10 m/s in a distance of 7.5 m. Determine the force of friction causing the puck to slow. Show all work.
2. A toy company hires you to construct a device that uses a small spring to launch 15 g foam pellets. The spring requires an average force of 5.70 N to compress it 1.30 cm. Determine the speed of one of the foam pellets as it leaves the spring. Show all work.
3. A spring having a constant of 44 N/m is initially compressed 4.0 cm. The spring is then compressed another 5.0 cm in a time of1.4 s. Determine the work done to compress the spring from 4.0 cm to 9.0 cm. Show all work.