Angular Momentum

Units

100

What is the symbol for angular momentum?

L

200

Angular velocity is measured in _________

Radians/second (rad/s)

300

Rotational Inertia is measured in _______

Kilogram meters²

(kg*m^2)

400

What is this unit equivalent to in terms of SI units? (kg, N, etc.)

N*m/s

Watt (W)

Equations

100

Inertia * Angular velocity = ______

Angular momentum

200

The equation for rotational kinetic energy is ______

1/2Iomega^2

300

Angular momentum is the cross product of what two quantities?

Radius and momentum

400

What is the equation for finding an object's center of mass?

x_(com)=(summ_ix_i)/(summ_i)

Definitions

100

An elastic collision differs from an inelastic collision because for inelastic collisions, _______ is not conserved

Kinetic Energy

200

In a(n) ____ collision, the objects will stick together and move with the same velocity

Inelastic

300

In an inelastic collision, angular momentum is conserved, but not rotational kinetic energy, because ____

Lpropomega,Kpropomega^2

400

The derivative of angular momentum with respect to time 

(dL)/(dt)

is equal to _____

Torque

Problems

100

An ice skater pulls his arms in during a spin. This will decrease his _____

Moment of Inertia

200

DAILY DOUBLE

If the radius vector points in the right (+x), and the momentum is out of the board (+z), the angular momentum will point ______

Down (-y)

300

Disk F is spinning clockwise. Disk G has half the mass of Disk F but is identical otherwise and is spinning counterclockwise at three times the speed of Disk F. When the two disks collide, which direction will the system be spinning?

Counterclockwise

400

The angular momentum vector of Earth about its rotation axis, due to its daily rotation, is directed

North

Final Jeopardy

500

Mr. Benzakein's wrist tattoo is related to angular momentum in a particular field of physics.

1. What field of physics?

2. What is the value of the tattoo?

1. Quantum Mechanics

2. H bar, or

h/(4pi)