An electronic package with a surface area of 1 m2 placed in an orbiting space station is exposed to space. the electronics in this package dissipate all 1850 w of its power to space through its exposed surface. the exposed surface has an emissivity of 1.0 and an absorptivity of 0.25. given: σ = 5.67×10–8 w/m2·k4

The energy equivalent of the rest mass of an electron is

3. a lunar exploration vehicle was created by a research team. it weighs 3,000 kg on the earth. it needs an acceleration of 10 m/s2 on the moon. in order to have the same acceleration, what will be the net force acting on the vehicle on the earth?

Two loudspeakers, 5.5 m apart and facing each other, play identical sounds of the same frequency. you stand halfway between them, where there is a maximum of sound intensity. moving from this point toward one of the speakers, you encounter a minimum of sound intensity when you have moved 0.33 m . assume the speed of sound is 340 m/s. part a) what is the frequency of the sound? part b) if the frequency is then increased while you remain 0.21 m from the center, what is the first frequency for which that location will be a maximum of sound intensity? express your answer to two significant figures and include the appropriate units.