What is the change in internal energy if 60 J of heat is released from a system and 30 J of work is done on the system? Use AU = Q-W.
A. 90 J
B. -90 J
C. -30 J
D. 30 J

F500 j of energy were added to 1 kg of each of these samples, which would experience the least temperature increase?

Avehicle has an oil leak that is causing the entire oil pan to be wet, but inspection reveals no exact source after cleaning off the oil residue. technician a says to install a fluorescent dye in the crankcase and operate the engine, then re-inspect for leaks with a special light (black light). technician b says the oil leak may be coming from a source at the top of the engine, such as a valve cover gasket. who is correct?

Given the position vector of the particle r(t)=(t+1)i+(t^2−1)j+2t k, find the particle's velocity and acceleration vectors at t=1