### Present Remotely

Send the link below via email or IM

• Invited audience members will follow you as you navigate and present
• People invited to a presentation do not need a Prezi account
• This link expires 10 minutes after you close the presentation

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.

# Total Mechanical Energy

By:Allison Johnson
by

## Allison Johnson

on 11 March 2011

Report abuse

#### Transcript of Total Mechanical Energy

MECHANICAL ENERGY. Energy cannot be transferred outside, IF in an isolated closed system. Since Potential Energy=U g =Mass x Gravity x Height, the bird's potential energy while sitting on
top of the tree is greater than it's potential energy would be standing on the ground. Say the mass of the bird is 10 kg and the height of the tree is 10 m. In the tree: Ug = Mgh = (10)(9.8)(10) =980 Joules On the ground: Ug = Mgh =(10)(9.8)(0) = 0 Joules Total Mechanical Energy= Mgh + 1/2mv 2 (Potential) (Kinetic) Mechanical Energy is the same at the top as the bottom.

If the mass of the box and height of the ramp are given and you want to find the speed (velocity), set the potential energy equal to the kinetic and solve. Mgh = 1/2mv. 2 Shortcut for velocity! Square root of 2gh 2 10 m/s 20 m 35 m 500 kg A B C D E The amount of total mechanical energy at points A, B, C, D, & E is the same. 60 m Mass of the cart: 500 kg
Height of point A: 60 m How will you find the speed of point D? Remember, the potential energy at point A is equal to the kinetic energy at point D.... so, you use Mgh = 1/2 mv. 2 Got an idea yet? An airplane nose dives from a height of 3000 m to 1800 m. To find the change in potential energy, you find the potential energy at its highest point and subtract the potential energy from the new height. Potential energy CAN be negative! Thanks for watching! By: Allison Johnson & don't forget the equation, Me= Ug + K! - olivewhite.com - course notes Source citations - Principles and Problems by: Holt
Full transcript