The escape velocity from the earth's surfave of Earth is 1.1×10⁴ms¯¹. What is the escape velocity from a point at a height of 0.2r from the Earth's surface? (radius of Earth is r)

If a clock aboard a space ship traveling at 0.900 c of the speed of light relative to earth chimes once at the beginning of the hour and again when it reads one hour later, how much time would an observer on earth say elapsed between the two chimes?

Clothes dryer uses about 7 amps of current from a 240 volt line. how much power does it use?

An architect plans to use solar energy to heat the next house he designs. what principle of absorption and infrared energy can be applied to the design of the new house? how could she apply to those principals?