What is the direction of the net force that acts on an object undergoing uniform circular motion? a. the direction of the force is opposite to the object's motion. b. the direction of the force is the same as the object's motion. c. the direction of the force is away from the center of the object's circular path. d. the direction of the force is toward the center of the object's circular path.

An air standard cycle with variable specific heats is executed in a closed system and is composed of the following four processes. 1-2 isentropic compression 100 kpa and 22°c to 600 kpa 2-3 v=constant heat addition to 1500 k 3-4 isentropic expansion to 100 kpa 4-1 p=constant heat rejection to initial state (a) show the cycle on p-v and t-s s (b) calculate the net work output per unit mass (409 kj/kg) (c) determine the thermal efficiency (47.9%)

Agust of wind pushes a beach ball with a force of 9 newtons. the ball rolls 10 meters in 3 seconds. what is the power of the wind?

2) the sun is wonderful source of energy. it is renewable and natural with few dangers. solar cells rely on the sun for energy. these cells would be more practical to use if they were