Download presentation

Presentation is loading. Please wait.

Published byDominick Alligood Modified over 2 years ago

1
Unit 3 Section 2 Lesson 2 Potential Energy PE Objectives Unit 3 Section 2 Lesson 2 Potential Energy Objectives: ▫ Show understanding of the Physics concept of Potential Energy ▫ Correctly identify Potential Energy from given situations ▫ Recall and show understanding of the formula to calculate Potential Energy ▫ Show understanding of the relationship between Potential and Kinetic Energy ▫ PE = mgh ▫ Do NOW: If you accelerate a 4.0 kg object from rest at 2.0 m/s 2 for 5.00 sec, what is the kinetic energy of the object? How much work was done on the object? ▫ Unit 3 Section 2 Lesson 2 HOMEWORK: ▫ Serway Pages 240 – 241 #’s 3, 5, 7, 13, 15, 21-22 ▫Unit 3 Section 2 Lesson 1 HOMEWORK: DUE MON Jan 14 ▫Serway PAGE:209 : #’s 27, 30, 31, 33, 34, 37, 40, 41 1

2
Potential Energy Potential energy is the energy possessed by an object as a result of its POSITION or CONDITION. Gravitational PE {GPE} ▫ In Physics, ground level is normally assumed to be at ZERO GPE. ▫ Any object that is at ground level has ZERO GPE. ▫ If object is lifted a certain height above ground, its GPE has increased. ▫ Elastic PE (not in syllabus) “Slinky” … when stretched or compressed Spring … when stretched or compressed Rubber band … when stretched Balloon with air … when compressed 2

3
In Class Gravitational PE Can be calculated with: GPE = mass gravitational height above acceleration ground level = mgh Units: [J] =[kg] * [m/s 2 ] * [m] SI Units of GPE : Joule [J] 3 Ground, 0 GPE Distance from ground, h Object on top of building, of mass, m g earth

4
In Class Example of GPE You lifted your 5.0 Kg book bag to the top of your table. What can you say about the GPE of your bag? ▫ Zero, increase, decrease Lift the same bag on the Moon. What happens to GPE? ▫ Zero, increase, decrease Will the GPE be the same on Earth and Moon? ▫ Same, less on Moon, more on Moon? 4

5
In Class Examples of GPE You lifted a set of books of mass 3.0 kg, for 2.0m. What is the GPE gained by the books? Take g=10m/s 2. Find the work done by you to lift the books. 5 ΔU g = GPE = mgh = 3 10 2 = 60 J Work done, W = F d (F = weight of books) = (m g) d = 3 x 10 x 2 = 60 J (Note: same as GPE)

6
Unit 3 Section 2 Lesson 2 PE {ΔU g } In Class 290/1 You Lift a 7.30 kg bowling ball from a storage rack and hold it up to your shoulder preparing to roll it down the lane for a STRIKE! The storage rack is 0.610 m above the floor and your shoulder is 1.12 m above the floor. How much work did you do lifting the ball from the rack to your shoulder? Elliot drops a 1.6 kg brick from the mansion roof 6.7 meters to the ground. ▫ What was the change in potential energy? A Warehouse worker picks up a 10.15 kg box from the floor and places it on a shipping table 1.15 meters above the ground. As he wraps the box for shipping, he slides it down the 3.5 m table to the end at a constant velocity in 21.0 seconds. He then lowers the box back to the floor. ▫ Ignoring friction, what was the total energy change of the box? Elliot drops a 1.6 kg brick from the mansion roof 6.7 meters to the ground. ▫ If all the potential energy was converted into kinetic energy, what was the velocity of the brick (no friction) when it hit the ground? 6

Similar presentations

OK

Chapter 5 Energy. Energy defined and Work Energy- is defined as the ability to do work. Work is done when a force causes something to move https://www.youtube.com/watch?v=xBnS23U_ao4.

Chapter 5 Energy. Energy defined and Work Energy- is defined as the ability to do work. Work is done when a force causes something to move https://www.youtube.com/watch?v=xBnS23U_ao4.

© 2017 SlidePlayer.com Inc.

All rights reserved.

Ads by Google

Ppt on disk formatting types Ppt on solid dielectrics for hot Thin film transistor display ppt online Ppt on column chromatography principle Ppt on earthquake in bhuj Ppt on measurement of price elasticity of demand Download ppt on computer vs books essays Ppt on traction rolling stock wheels Ppt on peak load pricing strategy By appt only-movie