Working out at about 60% to 75% of your maximum heart rate (the so-called fat-burning zone) burns fewer calories than working out at 75% to 85% of your maximum heart rate (the so-called aerobic or cardio zone).
In physics, motion is a change in position of an object with respect to time. Motion is typically described in terms of displacement, distance (scalar) , velocity, acceleration, time and speed.
Friction is the force that opposes the motion of an object. Learn about the sources of friction, identify examples of friction and test your knowledge with quiz questions.