Physics Library / Computational resource

Motion around a circle

Change the radius and speed. Watch the velocity turn while acceleration always points inward.

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Orbit and vectors

One revolution takes 3.93 s.

PathVelocityInward acceleration

The arrows show direction. Their lengths are scaled independently so both stay visible as you change values.

Position through one revolution

The x and y coordinates oscillate, even though the speed stays constant.

x = R cos(θ),   y = R sin(θ)

x / Ry / R
Angular speed1.6 rad/s
Period3.93 s
Frequency0.255 Hz
Inward acceleration12.8 m/s2
Inward net force25.6 N

Velocity is tangent to the circle. Acceleration points toward its center.