Uniform Circular Motion Review

A car is doing donuts in a parking lot. It completes 5 circles in 35 seconds. What is the period of rotation, in seconds?

Mathematical Equivalence

ON

A pig is flying in uniform circles with a period of 2 seconds. How many circles does the pig complete over ten seconds?

Mathematical Equivalence

ON

A object is traveling in uniform circular motion. It has a period of 6 seconds. The radius of the circle is 3 meters. What is the tangential velocity, in m/s?

(round to a whole number)

Mathematical Equivalence

ON

Answer explanation

v = 2πr / T

v = 2π(3) / 6

v = π

(round to 3)

The circumference of a circle is...

• 2πr

• πr

• πr²

• 2πr²

Two riders sit at positions X and Y. Do they have different periods of rotation and why / why not?

• No, because they have the same tangential velocity.

• No, because they take the same amount of time to complete 1 loop.

• Yes, because they have different tangential velocities.

• Yes, because they have different masses probably.

Two riders sit at positions X and Y. With every loop, do they travel the same distance?

• Yes, since they are on the same ride

• No, rider Y travels a greater circumference

A runner is running around a circular track. The track has a diameter of 15 meters. How many meters, in total, does the runner run when it completes one loop?

• Depends on how long it takes him to run the loop

• 47.12 meters

• 94. 94.25 meters

• 176.71 meters

The applied force is equal to 50 N. What is the net centripetal force?

• 50 N

• 43.3 N

• 25 N

• 0

Answer explanation

Centripetal is a direction that refers to forces that are perpendicular to the motion. This 50 N force has two components. One is parallel to the motion (43.3, or 50cos(30)) and one is perpendicular to the motion (25 N, or 50sin(30)). The one perpendicular to the motion is the only force directed centripetally, so it's our net centripetal force.

Tags

NGSS.HS-PS2-1

This car is ​ (a)   and also​ turning ​ (b)  

• speeding up
• slowing down
• traveling at a constant velocity
• right
• left

Tags

NGSS.HS-PS2-1

Which of the following is a correct derivation for tangential velocity?

• √(r/(ΣF_cm)) = v

• √(ΣF_crm) = v

• (√ΣF_c)r/m = v

• √(ΣF_cr/m) = v

Tags

NGSS.HS-PS2-1