Without the force of friction, people would not be able to walk. |
true |
The energy derived from the digestion of food is __________. |
chemical energy |
One consequence of Newton's third law of motion is that __________. |
all actions have opposite reactions |
Bill is throwing a football at four targets and attempting to knock them over. Which of the following targets will be hardest for him to knock over? |
the 150-gram nylon target |
The aerobic system starts producing energy during prolonged periods of light to moderate exercise. |
true |
Gravity is an attractive force that decreases as the mass of an object increases. |
false |
Real-world efficiencies are generally very high, in the 90 percent range. |
false |
Friction is a force in which two objects __________. |
slide agaisnt each other |
According to Newton's third law of motion, if you push against a wall, the wall will __________. |
push up agaisnt you with equal force |
Human movement involves the complex interplay of many body systems. |
true |