A computer cooled by a fan contains eight PCBs, each dissipating 10W power. The height of the PCBs is 12 cm and the length is 18 cm. The cooling air is supplied by a 25 W fan mounted at the inlet. If the temperature rise of air as it flows through the case of the computer is not to exceed 10 C, determine (a) the flow rate of the air that the fan needs to deliver and (b) the fraction of the temperature rise of air that is due to the heat generated by the fan and its motor.

Alarge truck is moving 22.0 m/s. if it’s momentum is 125,000 kg • m/s, what is the trucks mass

Aperson walks first at a constant speed of 4.89 m/s along a straight line from point a to point b and then back along the line from b to a at a constant speed of 2.95 m/s. what is the average speed over the entire trip?

An alpha particle with kinetic energy 12.5 mev makes a collision with lead nucleus, but it is not "aimed" at the center of the lead nucleus, and has an initial nonzero angular momentum (with respect to the stationary lead nucleus) of magnitude l = p0 b, where p0 is the magnitude of the initial momentum of the alpha particle and b=1.40×10−12 m. (assume that the lead nucleus remains stationary and that it may be treated as a point charge. the atomic number of lead is 82. the alpha particle is a helium nucleus, with atomic number 2.) what is the distance of closest approach?