Apoint source of light is 80.0 cm below the surface of
a body of water. find the diameter of the circle at the surface
through which light emerges from the water.

Two particles of masses m and 2m are placed on a smooth horizontal table. a string, which joins these two masses, hangs over the edge supporting a pulley, which suspends a particle of mass 3m.the pulley has negligible mass. the two parts of the string on the table are parallel and perpendicular to the edge of the table. the hanging parts of the string are vertical. find the acceleration of the particle of mass 3m.

After a car's engine has been running for a while, if you stand near the car's engine you can often feel heat coming from the engine as a result of a. radiation b. convection c. conduction

Apulley with a mechanical advantage of 5 will require you to pull times the amount of rope. a. 1/5 b. 5 c. 10 d. 15