A 4500-kg spaceship is in a circular orbit 220 km above the surface of Earth. It needs to be moved into a higher circular orbit of 390 km to link up with the space station at that altitude. In this problem you can take the mass of the Earth to be 5.97 × 1024 kg. show answer Incorrect Answer How much work, in joules, do the spaceship’s engines have to perform to move to the higher orbit? Ignore any change of mass due to fuel consumption.

Asquare isothermal chip is of width w=5 mm on a side and is mounted in a substrate such that its side and back surfaces are well insulated; the front surface is exposed to the flow of a coolant at tinf=15 °c. from reliability considerations, the chip temperature must not exceed t=85 °c. if the coolant is air and the corresponding convection coefficient is h=200 w/m2 x k, what is the maximum allowable "power" of the chip? if the coolant is a liquid for which h=3000 w/m2 x k, what is the maximum allowable power of the chip?