Question

Explain accelerated motion

Answer 1

Any acceleration of an object necessarily implies a net force in the direction of acceleration. In an environment with negligible friction, a constant force of uniform magnitude produces constant and uniform acceleration. In the case of gravitational acceleration mentioned above, the constant force is gravity, which accelerates an object toward the gravitational center of another mass. This is true even if the initial direction of motion is opposite to the gravitational force, like a ball thrown straight up, because deceleration in one direction is equivalent to acceleration in the opposite direction. In the case of an orbiting object such as a planet, the force of gravity accelerates the body not in the direction of motion, nor in the opposite direction, but at a right angle to it. This is similar to the centripetal forces that hold together the materials of a spinning wheel.

Answer 2

Answer:

If an object having initial velocity u attains a velocity v after a time t, then acceleration a = (v - u/t. When velocity of an object increases with time, then acceleration is positive. If velocity of an object decreases with time, then acceleration is negative. Negative acceleration is also called retardation. Acceleration can be uniform or non-uniform. A freely falling body has a uniform acceleration of 9.8 m/s2 When a car moves with variable velocity, then the acceleration of car is non-uniform. For an object moving with uniform velocity, the acceleration is zero.