Circular Motion Flashcards

Flashcards on Circular Motion

What is one radian?

Angle subtended by a circular arc with a length equal to the radius of the circle.

How do you convert an angle from degrees to radians?

Divide the angle in degrees by 360 and then multiply by 2π.

What is the period, T, in circular motion?

The time taken for an object to travel a full circle.

What is frequency, f, in circular motion?

The number of full circles completed in one second.

What is the formula relating frequency (f) and period (T)?

f = 1/T

What is angular velocity, ω?

The rate of change of angle.

What is the formula for angular velocity?

ω = θ/t

What are the units for angular velocity?

rads-1

What is another formula for angular velocity involving period or frequency?

ω = 2π/T = 2πf

What happens to the velocity of an object moving in a circle, even if its speed is constant?

The velocity of the object is constantly changing.

What is centripetal force?

Net force acting perpendicular to the direction of velocity, towards the center of the circle.

What is the formula for the speed, v, of an object moving in a circle?

v = 2πr/T = ωr

What is the formula for centripetal acceleration?

a = v^2/r = ω^2r

What is the formula for centripetal force using mass, velocity, and radius?

F = mv^2/r = mω^2r

Where can centripetal force come from?

Gravitational fields, friction, tension in a rope

What is important to remember about centripetal force when multiple forces are acting?

The net force acting towards the center of the circle.

How can circular motion be investigated experimentally?

By tying a bung to a string and whirling it around a glass tube with a weight suspended at the end.

In the experiment with the bung and string, what provides the centripetal force?

Mg

What equation relates the centripetal force provided by the weight to the mass and velocity of the bung?

Mg = mv^2/r

How can the velocity of the bung be determined in the experiment?

Measure the radius of the circle and the time for one complete oscillation.

What should be produced when v^2 is plotted against M in the bung experiment?

A straight line graph passing through the origin.

How many radians are in a full circle?

There are 2π radians

What is the equation that relates frequency to period?

f = 1/T

What is the unit of measurement for angular velocity?

Radians per second (rads-1)

When an object travels in a circle, why is it accelerating even if the speed is constant?

The direction is constantly changing