7. The European Space Agency launched a probe called Rosetta in March 2004. In August 2014, Rosetta reached its destination: a comet called 67P/Churyumov-
Gerasimenko. Rosetta is the first spacecraft to rendezvous with a comet. It contained a
lander craft, called Philae.
The Rosetta has a launch mass on Earth of 3000 kilograms [kg] and the Philae
has a launch mass of 220 pound-mass (lb). In order to escape Earth's gravity,
the combined spacecraft must accelerate at a rate of 25,000 miles per hour
squared (mi/h²]. How much thrust, in units of newtons [N], must the engines
provide to reach this acceleration?

Athin walled concentric tube exchanger is used to cool engine oil from 160°c to 60°c with water that is available at 25°c acting as a coolant. the oil and water flow rates are each at 2 kg/s, and the diameter of the inner tube is 0.5 m and the corresponding value of the overall heat transfer coefficient is 250 w/m2. oc. how long must the heat exchanger be to accomplish the desired cooling? cpwater=4.187 kj/kg-candcpengine el=2.035 kj/kg·°c, oil . 120]

Acountershaft is supported by two tapered roller bearings using indirect mounting. the radial bearing loads are 1120 lb for the left-hand bearing and 2190 lb for the right-hand bearing. the shaft rotates at 400 rpm and is to have an l10 life of 40,000 hours and an application factor of 1.4. assume ka2k 15, and find the required radial rating of each bearing

An array of m-50 thermoelectric modules is installed on the exhaust of a sports car. each module has an effective seebeck coefficient of sp of 0.143 5vk and an internal electrical resistance of r.-4 ? in addition, : (15 points each module is of width w 60mm and contains n=100 pairs of semiconducting pellets. each pellet hasan overall length of 2l-5mm and a cross-sectional area as 1.2 x 10'm and is characterized by a thermal conductivity of kpl2w rnk. the hot side of each module is exposed to exhaust gases at·p650c with hia4ow rrk while the osite side of each module is cooled by pressurized water at surface) and 156 °c (at the cool surface). 11s c with h: -500w/m'k. the modules are wired n series and the load resistance is r d=400ohm .the module surface temperatures, t, and ts are 183 "c (at the hot surface and 156c (at the cool surface) a)-draw a schematic of this scenario and label all parts. a. b. if the induced current, i, is 0.15 amps, what is the total power (pa) for one module? c. what is the total power harvest from the exhaust with all 50 modules?