CENTRIPETAL FORCE

Centripetal force is define as a force that keeps a body moving with a uniform speed along a circular path and its directed along the radius towards the center. Its direction is the same direction of the centripetal acceleration. If the centripetal force suddenly stop to act on a body in the circular motion, the body flies off in a straight line with constant tangential speed. For a circular motion to occur, there must be a constant force acting on the a body pushing it toward the centre of the circular path, that is centripetal force.

COURCE OF CENTRIPETAL FORCE

To make a body or object move in circular path, there must be source of centripetal force to occur. For example, a planet orbiting the sun, the centripetal force is supplied by gravitational force. For non-circular orbits or trajectories, only the component of gravitational force directed orthogonal to the path (toward the center of the osculating circle) is termed centripetal; the remaining component acts to speed up or slow down the satellite in its orbit. For an object swinging around on the end of a rope, the internal tensile stress in the centripetal force an another example is for an electron orbiting the atom, it is electrical. There are other example that apply centripetal force in daily life that is when we drive car, train moves, people play the ferris wheel and many more.

FORMULA

The magnitude of the centripetal force on an object of mass m moving at tangential speed, v along a path with radius, r is: 

F = mac = mv²/r

Where uc is the centripetal acceleration. The direction of the force is to word the center of the circle in which the object is moving or the osculating circle, the circle that best fits the local path of the object, if the path in not circular. The speed in the formula is squared, so twice the speed needs four times the force. The inverse relationship with the radius of curvature shows that half the radial distance requires twice the force. This force is also some times written in terms of the angular velocity, ω of the object about the center of the circle:  

F = mω²

APPLICATION OF CENTRIPETAL FORCE IN SPORTS

• Swing Hammer

In order swing the hammer in a circle, the thrower must be able to exert a sufficient centripetal force on the chain. Notice how the angle of his leg and foot enable him to do this. Hence when athlete throw the metal ball, they not fall in the ground.

• Car Racing

We can see that centripetal force is applied in car racing. The extreme banking of curves on a race trick allows the cars to maintain high speeds through the turn. This force can avoid and reduce the skidding and friction force between the car and the road.

• Ice Skating

Ice skating provides sample opportunity to test variations of centripetal force. During pairs skating death spiral spin, for instance, one skater acts as the center of the circle while his partner rotates around him. He provides tension force, which acts upon his partner to initiate the centripetal force. The faster his partner spins, the more force is needed to keep her moving in a circle. His partner’s inertia, or tendency to resist a change in motion, is based on her density; the higher the density, the greater the inertia. This move is best performed with a stronger and heavier center or pivot point to maintain the centripetal acceleration.