PLEASE HELP Much information gained by today's astronomers in developing new theories about the universe comes PRIMARILY from

A) backyard observers like yourself.

B) astronomical records from archeaological digs.

C) powerful x-ray and radio telescopes that can see far in the universe.

D) future-thinking science fiction writers and screenplays from movies like "Contact".

The motor m applies a time-varying force of f (200 t) n, where t is in seconds. box b with mass 200 kg starts from rest, and the coefficients of kinetic and static friction are 0.2 and us 0.3 the acceleration due to gravity is g 9.8 m/s2 b 300 a) find the time ' when the box starts to move. b) calculate the speed of the crate at 3 s c) calculate the power delivered by the motor at t 3 s

The speed of sound in ice, water, and steam is shown. what best explains the speed of sound in different states of matter? sound travels fastest in ice because energy is easier to transfer when the molecules are close together. sound travels slowest in steam because the sound has to move around the gas molecules that are far apart. sound travels fastest in ice because the temperature of solids is always greater, so the heat transfers the sound energy. sound travels slowest in steam because the pressure is so great the sound cannot travel though the steam particles.

If jerome is swinging on a rope and transferring energy from gravitational potential energy to kinetic energy, is being done.