PLEASE HELP What is the change in internal energy if 80 J of thermal energy is released
from a system, and 30 J of work are done on the system? Use AU = Q-W.

Delta U = 30 - 80; -50 jules

Explanation:

The system is losing 80 J, but it is also gaining 30 J because the surroundings are doing work on it. So the net change in energy is -50 J

a. are

initial speed when it is dropped is 150 ft/s

now at the same moment the acceleration due to gravity is perpendicular to its velocity

so as we know that

now we have centripetal acceleration a = 32 ft/s^2 as its perpendicular to velocity

while tangential acceleration at the same moment will be zero

so

now radius of curvature is given as

so the radius of curvature just after it is dropped is 703.125 ft