Help???centripetal acceleration????

Question

can someone help understand that an object is actually accelerating inward in a circular motion? i mean, i can only see the object is traveling a constant velocity but i just can not see it is accelerating.

Answer 1

It is easy to understand acceleration in a straight line. Since acceleration is the change in velocity, either something is moving faster or its not. Because acceleration is just that, the change in velocity.
For centripetal acceleration, remember that velocity is not just the speed, but also the direction something is moving. Therefore, even though something moving around a circle may not be increasing the magnitude of the velocity(constant speed), the direction is always changing. Thus, the resultant change is called centripetal acceleration .

Answer 2

The key fact to remember is that velocity is defined by both magnitude and direction. For example, going 60 mph north is not the same as going 60 mph south.

Then, by definition, the change in velocity over time is called acceleration (in math talk, this is often written as dv/dt = a). Because velocity has both magnitude (e.g., the 60 mph) and direction (e.g., the north or south), a change in either magnitude, direction, or both results in some acceleration.

So what's changing in a "circular motion"? Well, at least the direction is changing. It has to; otherwise the object would be going off straight or some other, non-circular direction. Thus, at a constant speed (the magnitude like 60 mph) the velocity is changing because the direction is constantly changing. And that change in direction results in acceleration that can produce a force.

If you swing your object at the end of a string around your head, the object is constantly changing direction...it is accelerating. One of Newton's laws says that an object in motion will travel in a straight line unless acted on by a force to change that. The string pulls on your object as you swing it around your head. That's the force that keeps changing the object's direction so it goes around in that circle above your head. That force is called centripetal force and that constant change in the object's direction is the acceleration you are callling "centripetal acceleration."

Answer 3

just imagine a car wheel while accelerating the car.... now put a small ring around a rod attached to the wheel, since the object would fly off along a straight line without anything keeping it there there must be a force holding it in place (F=m*a); iknow it's hard the first time, but take the solar system for example - things would fly along a staight line without centripetal acceleration - thanks god we have gravity which is our force, so gravity/mass is the centripetal acceleration!

just look it up in a physicsbook if my explanation is insufficient

Answer 4

Well, gravity is acceleration as well, and I have trouble visualizing that one. All calculations of gravity only make sense as acceleration. And if you are in a closed elevator, there is no experiment you can do inside to determine if the gravity you feel is from actual gravity or from acceleration. So we call them the same.

I was also about to add what the guy under me put, but he explains it fine.