Circular Motion: Why an Object Moves When Acceleration is Perpendicular

[songoku]

Why an object will move in circular when the acceleration is perpendicular to the velocity?

 

[FactChecker]

If the acceleration is always perpendicular to the linear velocity, then the linear velocity will never change. That means that the acceleration is always a rotational acceleration.

 

[sophiecentaur]

Why an object will move in circular when the acceleration is perpendicular to the velocity?

It may not be intuitive to you but read FactChecker's reply carefully (and rigorously). His argument is sufficient if you follow his logic.

 

[pixel]

Why an object will move in circular when the acceleration is perpendicular to the velocity?

Acceleration causes a change in velocity. But velocity is a vector quantity with a magnitude (speed) and a direction. In circular motion with constant speed, the direction of the velocity is constantly changing and the change in velocity points toward the center of the circle. That is the direction of the acceleration.

Look at the diagram here: http://ibphysicsstuff.wikidot.com/uniform-circular-motion It shows the velocity vector at two different times as well as the difference v₂ - v₁ (the blue vector). If you imagine the two instances (blue dots) to be closer together, you can see that the difference vector would point toward the center, perpendicular to the velocity. That difference vector is in the direction of the acceleration.