You push a 4.9 kg block against a horizontal spring, compressing the spring by 16 cm. then you release the block, and the spring sends it sliding across a tabletop. it stops 77 cm from where you released it. the spring constant is 220 n/m. what is the coefficient of kinetic friction between the block and the table?

At 20∘c, the hole in an aluminum ring is 2.800 cm in diameter. you need to slip this ring over a steel shaft that has a room-temperature diameter of 2.804 cm . 1. to what common temperature should the ring and the shaft be heated so that the ring will just fit onto the shaft? coefficients of linear thermal expansion of steel and aluminum are 12×10−6 k−1 and23×10−6 k−1 respectively.