Astronomers have measured the velocity of a star to be 30 km/s toward us. What did they need to observe to make this measurement

A500g object falls off a cliff and losers 100 j from its gravitational potential energy store. if the gravitational field strength g=9.8n/kg, how high is the cliff?

Apair of 10μf capacitors in a high-power laser are charged to 1.7 kv. a. what charge is stored in each capacitor? b. how much energy is stored in each capacitor?

Sound is a disturbance that travels through a medium as a