Circular Motion Level 2 NCEA

The ​ (a)   is a force that acts directly ​ (b)   the center of the circular motion, the same direction as the ​ (c)   . The velocity in circular motion always acts ​ (d)   to the circle.

• centripetal force
• towards
• away from
• tangential
• centripetal acceleration

Match the following situations to the force that supplies the centripetal force needed

• A satellite in orbit around Earth

• Tension

• A rope being swung around in circles

• Gravity

• A car going around a corner

• Friction

Label the vectors

a

b

Centripetal Acceleration

Velocity

Speed

In circular motion, the ​ (a)   can be constant even if there is an ​ (b)   . This is because ​ (c)   is speed and ​ (d)   , so even if the speed is constant, the direction of the velocity vector is always changing, so an acceleration must be present.

• speed
• acceleration
• velocity
• direction

Which of the pictures has the velocity and centripetal force in the correct direction?

• A

• B

• C

• D

The centripetal acceleration points

• Away from the centre of the circle.

• Towards the centre of the circle.

• Tangentially from the circle.

The centripetal force points

• Away from the centre of the circle.

• Towards the centre of the circle.

• Tangentially from the circle.

The velocity vector points

• Away from the centre of the circle.

• Towards the centre of the circle.

• Tangentially from the circle.

If the speed increases, the size of the centripetal force ​ (a)   .

If the radius of motion increases, the size of the centripetal force ​ (b)   .

If the mass of the object decreases, the size of the centripetal force ​ (c)   .

• increases
• decreases
• stays the same

Which of the following best describes the motion of an object in uniform circular motion?

• Constant speed and constant velocity.

• Constant velocity with changing speed.

• Constant speed with changing velocity.