Who told you that? As an aside, I suggest you read an introductory Physics text to learn the difference between an applied force e. The force toward the center, which keeps the object in orbit, is centripetal force. It can come from various sources: gravity, EM, tension in a string, etc. It is a fair question. Anupam hits the nail on the head, by the way.
Do you know about centrifugal force too in detail? To answer the first line of your question i have to explain the cause of centrifugal force. Show 1 more comment. Active Oldest Votes. Improve this answer. Glorfindel 1, 1 1 gold badge 14 14 silver badges 20 20 bronze badges. Nor it is inertia guided. It only comes into play when we switch our frame of reference to a revolving one. This appears to hold Newton's second law.
I edit my answer soon. Add a comment. If they would have applied the Law, they would have seen that the centrifugal force is equal and opposite the centripetal force.
Centrifugal force is an inertial force that resists changing the direction or velocity of the object. If you place an object on a disk and start it spinning, the friction holding the object on the disk is the centripetal force causing the object to move in a curved path. Once the disk spins fast enough, the centrifugal inertial force can become greater than the centripetal friction force holding the object in place. The object will then fly off in a straight line. Ball flies off spinning disk in straight line due to centrifugal force overcoming friction.
A related example is the amusement park ride, Round-Up , which consists of a circular platform that has a vertical cage-like wall around the edge. Ref: Amusement Ride Extravaganza. When the platform spins at a high enough rate, the centrifugal inertial force pushes the riders against the wall, holding them in place as the platform changes directions.
Although the riders feel a force pushing them against the wall, there is no real force or agent that is doing the pushing. It is simply an effect of inertia. Another amusement park ride that shows the centrifugal force is the roller coaster. Here is a quick overview of what a force is. I previously talked about real vs. For me, I say that if the force is essentially one of the 4 fundamental forces then it is "real". With this definition, centripetal force would be real and centrifugal not real.
Centripetal force is the force needed to make something move in a circle. Well, maybe it would be better to say that centripetal force is the force needed to make something change direction.
A constant magnitude centripetal force that is always perpendicular to the direction of motion will make the object move in a circle. It is important to note that centripetal force is still some force.
For instance, suppose you swing a rock around your head with a string. There is a force acting on the rock to make it move in a circle. This force is the tension in the string which is a real, fundamental force based on the electrostatic interactions between atoms. In this case, the tension would be the centripetal force. Another example - a car moving in a circular path.
In this case there is a centripetal force, it would be the frictional force between the tires and the road. In both of these examples, if you take away the centripetal force break the string or drive on ice , the object would move in a straight line. Most textbooks use the centripetal force term and use it correctly. Category: Physics Published: December 15, The centrifugal force is very real if you are in a rotating reference frame.
It causes objects in a rotating frame of reference to accelerate away from the center of rotation. Washing machines, uranium enrichment centrifuges, and biology lab centrifuges all depend on the reality of the centrifugal force.
However, the centrifugal force is an inertial force, meaning that it is caused by the motion of the frame of reference itself and not by any external force. If I stand on the ground and watch children spinning on a playground toy then in my stationary frame of reference their outward acceleration is caused simply by their inertia. In my frame, which is external to the rotating frame, there is no centrifugal force at work. But in the rotating frame of reference of the children, there is a centrifugal force.
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