A 71.80 kg person holding a steel ball stands motionless on a frozen lake. The person then throws the ball, which propels the person at 0.15 m/s to the
right and the ball 3.50 m/s to the left. If the initial momentum of the system is
zero, what is the mass of the steel ball?
A. 3.08 kg
B. 3.50 kg
O C. 20.51 kg
O D. 23.33 kg

What are the three ways that an object can accelerate

Ahair dryer is basically a duct in which a few layers of electric resistors are placed. a small fan pulls the air in and forces it through the resistors where it is heated. air enters a 1200 w hair dryer at 100 kpa and 22°c and leaves at 47°c. the cross-sectional area of the hair dryer at the exit is 60 cm2. neglecting the power consumed by the fan and the heat losses through the walls of the hair dryer, determine (a) the volume flow rate of air at the inlet and (b) the velocity of the air at the exit.

Which best term to describe a chemical reaction that absorbs energy from its surroundings? a. thermal conductor b. thermal insulator c. endothermic d. exothermic