Why does an object traveling in a circular path at constant speed accelerate?

Question

Why does an object traveling in a circular path at constant speed accelerate?

Answer 1

if you look at the orbit of the earth, it is elliptical yet the earth dos not accelerate in the direction of its orbit. it accelerates toward the sun. the net resultant of the forces, which is just adding gravitational force to the force of inertia in the forward direction, the two create an elliptical orbit. the same would apply to perfectly circular orbit. it would accelerate toward the center.

Answer 2

Hmmm.  Forget the answer about the sun and the earth, that has gravity in the equation.  Your simple question says an item has a constant speed, but it accelerates.  It cannot be both.  It either has a constant speed or it accelerates.  Which is it?

Answer 3

Because it is changing its velocity. Remember that velocity has a direction and a speed.

Answer 4

Acceleration is the timed rate of change of velocity.  Velocity, as you are well aware, is a vector, thus it has magnitude and direction.  Everyone used to solving physics problems do so mostly in linear fashion.  However, if you look at my first sentence and set it up algebraically:

A = d/dt(V)

A = d/dt(Vmagnitude + Vdirection)

A = dV/dt magnitude + dV/dt direction

So if you are travelling in a circular path at constant speed your velocity magnitude may be constant, but your direction is constantly changing, thus you are accelerating.

Answer 5

It doesn't because if it were to accelerate it would not be a constant speed.