Astronomers observe several distant superclusters moving away from Earth. Explain how they can use spectral lines of light coming from the superclusters to identify which is receding from Earth at the slowest rate

The man fires an 80 g arrow so that it is moving at 80 m/s when it hits and embeds in a 8.0 kg block resting on ice. how far will the block slide on the ice before stopping? a 7.1 n friction force opposes its motion.

True or false: the revolution of the earth creates day and night as it rotates around the sun

In a system, when potential energy decreases, then entropy also decreases. true false