Motion is relative to an observer or to an object. For example, a woman driving a car is not in motion relative to the car, but she is in motion relative to an observer standing on the side of the road.Know More
A similar example is a cat sleeping on a rug. The cat appears to be at rest to an observer on Earth, but relative to an object at a fixed point in space, the cat is moving as fast as the Earth turns. As these examples show, discussions of motion must include a point of reference, especially when calculating measurements such as speed. For example, if a train is traveling 90 miles per hour and a man walks from the back of a train car to the front, how fast is the man moving? The answer depends on the point of reference. To another passenger in the train, the man is moving at a rate much less than 90 miles per hour. To an observer outside of the train, however, the man is moving at a rate slightly more than 90 miles per hour.
Most people consider motion relative to a fixed point on the Earth. Physicists consider that the universe has no fixed point, so all motion is relative to what is defined as a fixed point. In fact, this basic idea is part of Einstein's theory of relativity.Learn more about Motion & Mechanics
Kinetic energy is used by exploiting the motion of an object. For example, the energy of a moving piston in an automotive engine provides transportation. The kinetic energy of moving water powers hydroelectric dams that provide electricity.Full Answer >
Energy of motion is the energy an object possesses due to its motion, which is also called kinetic energy. This means that the object, which has energy of motion, can do work on any object it hits.Full Answer >
The path taken by a flying object in motion on the surface of the Earth is called a parabola. A parabola is a symmetrical arc, and the trajectory of flying objects with negligible air resistance in a gravitational field, as on the surface of the Earth, follows this path.Full Answer >
Force and motion are related because exerting force on an object causes a change in motion. An example would be kicking a ball to propel it forward. Two examples of natural forces are gravity and magnetism.Full Answer >