Unit 5 - Rotational Motion 🔄

What must happen to an object to be in Circular Motion?

--> What is Centripetal Acceleration?

- Am object needs to be moving in a perfect circle at a CONSTANT speed to be considered Circular Motion.

- Centripetal Acceleration is the accel on an object towards the centre of the circular motion

FORMULA: a = v^2/r OR 4pi^2r/T^2

What is a period, symbol, and units??

What is Frequency, symbol, units, and formula?

Period = time taken to travel once around a circle.

--> symbol is T cus its time (s)

--> T = 1/f

Frequency = #of cycles per time so F = 1/T

--> symbol is f and units are Hz

What are the 2 types of acceleration we can use for Uniform Circular Motion?

1. a= v^2/r

2. a = 4pi^2r/ t^2

What is the TRUE definition of centripetal force/accel?

Centripetal force or accel is the net name for NET force or accel.

--> This is because the centripetal force/accel is the only force/accel

What 3 steps do you need to find the tension in a string of a pendulum?

1. The 1st eq will be that Ftcosθ = mg.

--> The 2nd eq will be Ftsinθ = m4π^2r/T^2

(because Ftsinθ only find the tangent force to the curved motion of the pendulum)

2. ummmm find out later ig

What will we use for distance in Rotational Kinematics?

--> What are the new symbols?

--> How have the Kinematic formulas been changed?

- We will use the Radian for distance

- The new symbols are :

θ = angular pos/disp (in radians)

ω = angular velocity (rad/s)

α = angular accel (rad/s^2)

In rotational kinematics, what is the new formula for velocity?

--> what is the new acceleration formula?

tangential velocity (v)= rω

--> a = ω^2r

In Rotational Inertia ("moment of inertia"), what is:

- Mass

- Newton's 2nd law in relation to Torque

- Units of I (I = moment of inertia)

interia = the property of matter that resists changes to an object's state of motion

- Mass = AMOUNT of inertia

- Newton's 2nd law in angular form states: Tnet = Iα where

α = angular accel

I = moment of inertia of a mass or sys of masses