Car2 passes car 1. To a stationary observer, car 1 has a velocity of 13 m/s to the east and car 2 has a velocity of 16 m/s to the east. How much time will pass before car 2 is 20 m ahead of car 1?

How have the competing explanations' experiments on atoms affected the development of the atomic model?

Given the position vector of the particle r(t)=(t+1)i+(t^2−1)j+2t k, find the particle's velocity and acceleration vectors at t=1

Asolid cylinder and a cylindrical shell have the same mass, same radius, and turn on frictionless, horizontal axles. the cylindrical shell has light-weight spokes connecting the shell to the axle. a rope is wrapped around each cylinder and tied to blocks of equal masses that are held the same height above the ground. both blocks are released simultaneously. the ropes do not slip. which block hits the ground first? or is it a tie?