Velocity is distance traveled over?

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.

How do you count the total number of atoms present on one side of a chemical equation?

Aforce or 500 n separates two objects the distance between their centers is 67 m the first object has a mass of 20kg what is the mass of the second