1. An 18.0 kg sled is slding across a smooth, flat stretch of snow when a boy pushes it, causing it to speed up to 4,50 m/s in 3.75 s without changing direction. If the average force exerted by the boy
on the sled in its direction of motion was 12,5 N, with what initial velocity was it moving?

Which notation is used to represent an alpha particle? a. b. c. d.

The energy released by a nuclear fusion reaction is produced when

Two manned satellites approaching one another at a relative speed of 0.550 m/s intend to dock. the first has a mass of 2.50 ✕ 103 kg, and the second a mass of 7.50 ✕ 103 kg. assume that the positive direction is directed from the second satellite towards the first satellite. (a) calculate the final velocity after docking, in the frame of reference in which the first satellite was originally at rest.(b) what is the loss of kinetic energy in this inelastic collision? (c) repeat both parts, in the frame of reference in which the second satellite was originally at rest. final velocity(d) loss of kinetic energy = ?