torque and angular acceleration torque = = #nm -a force acting at a distance away from a pivot...

Torque and Angular AccelerationTorque = = #Nm

-a force acting at a distance away from a pivot

-causes a twist-torque is vector

-direction is oftenClockwise (CW)Counterclockwise (CCW)

= F r or = I

Torque and Angular Acceleration

Why is a door knob located as far as possible from the door hinge?

Torque and Angular Acceleration

Why is a door knob located as far as possible from the door hinge?

-You increase the “lever arm”

Hinge

Doorknob

Torque and Angular Acceleration

Torque’s unit is Newton meters

-Units of energy1Nm = 1J

-Never use Joules as a unit for torque.

Torque and Angular Acceleration

Newton’s First Law (revisited)-An object at rest will remain at rest, an object rotating will remain rotating, unless acted upon by an unbalanced outside torque

Torque and Angular Acceleration

Static EquilibriumTwo Conditions

-Forces must be balanced-Torques must be balanced

Torque and Angular Acceleration

Static Equilibrium ScenarioTwo Forces are balanced

N

mg

Torque and Angular Acceleration

Static Equilibrium ScenarioTwo Torques are balanced

Mass 1= 50 gramsRadius 1 = 10 cm Mass 2= 100 grams

Radius 2 = 5 cm

H:\IP Sims\Rotational Dynamics\Net Torque Example.IP

Torque and Angular Acceleration

Let’s look at an example where torques are not balanced

Click here…

Torque and Angular Acceleration

Ladder Example (Ladder is at rest)

Ground

Wall

Torque and Angular Acceleration

Ladder Example (Ladder is at rest)

Ground

Wall

Torque and Angular Acceleration

Ladder Example (Ladder is at rest)

Ground

Wall

Ff1

Ff2

N1

N2

mg

Credits

Tunes by…

Guru

Credits

Host

MC Webb

Funky Beats by…

Guru