Human Impact on Environment

Follow this link to view the interactive and complete your assignment.

Sound Answer Keys - Quiz Review

Answer keys for class handouts on sound:

Speed of Sound

Doppler Effect

Nature of Sound

Properties of Sound

Levels of Organization resources

Find the video song lyrics at this link.

Use the PowerPoint document at this link to begin creating your own video presentation about levels of organization in biology.

Fracking: Positive or Negative Impact?

Watch this video clip from PBS Newshour on fracking impacts, positive and negative.

Momentum, Impulse and 3rd Law Test Review

Test next class (20 questions)

Take a moment and review Newton's 3rd Law in a previous post, then review momentum and impulse from this week's lessons.

Use the answer key links below to check your understanding of Impulse and Momentum.

Impulse and Momentum - Check Your Understanding

Momentum, Impulse and Momentum Change

Notes slides on momentum and impulse HERE

Read...

Momentum and Impulse Connection

Conservation of Momentum

Watch...

Momentum and Impulse

Conservation of Momentum

KE PE Answer Key

Use the link below to view the answer key for the Energy handout in class yesterday.  (You'll need Adobe Acrobat Reader to view the file)

Remember, there will be a 10-question quiz in class using questions from this worksheet.

Energy Answer Key

Conservation of Momentum

We've discussed what momentum is (momentum = mass times velocity, or p = m x v). Now consider what happens when two objects interact, each with their own momentum.

Big Idea!      Momentum is always conserved (saved).

Consider a bat hitting a baseball. The law of conservation of momentum says that the total momentum of the bat and the ball before they collide will be exactly equal to the momentum of the two objects after the collision. We call these two objects a system. In other words, the total momentum considered to be conserved involves only these two objects. Both objects will change speed or direction once they collide but we know that their combined momentum before they collide will be exactly equal to their combined momentum after the collision.

Consider the example below.

Because the total of both car and truck after the collision must also be 30,000 kg m/s, a simple algebraic equation allows us to solve for the velocity of the truck after.

Check out Paul Hewitt describing this concept in a screencast here.

The Physicsclassroom.com provides an excellent description of the conservation of momentum here.