What is the potential energy of a board placed on the edge of a roof?

Click For Summary
SUMMARY

The potential energy (PE) of a board weighing 22 lb placed on the edge of a roof 28 ft above the ground is calculated using the formula PE = mgh. The correct gravitational constant to use in this scenario is 32.2 ft/sec², not 9.8 m/sec², as the latter is applicable in metric units. Therefore, the accurate calculation for potential energy yields a result of 1984 ft·lb.

PREREQUISITES
  • Understanding of potential energy concepts
  • Familiarity with the formula PE = mgh
  • Knowledge of gravitational constants in imperial units
  • Basic arithmetic operations
NEXT STEPS
  • Research the differences between metric and imperial units in physics
  • Learn how to convert between different units of measurement
  • Explore potential energy calculations in various contexts
  • Study the implications of gravitational constants in different environments
USEFUL FOR

Students in physics, carpenters needing to understand load safety, and anyone interested in the practical applications of potential energy calculations.

lilaznjewel
Messages
13
Reaction score
0

Homework Statement


A carpenter places a board weighing 22 lb on
the edge of the roof 28 ft above the ground.
How much potential energy does the board
have in relation to the ground?
Answer in units of ft · lb.


Homework Equations


PE=mgh


The Attempt at a Solution


I followed the formula 22*9.8*28 and i got 6036.8
 
Physics news on Phys.org
lilaznjewel said:

The Attempt at a Solution


I followed the formula 22*9.8*28 and i got 6036.8
You are using 9.8 m/sec^2 for g. You have use 32.2 ft/sec^2 when you use units of feet and lbs.

AM
 

Similar threads

Replies
44
Views
7K
  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 23 ·
Replies
23
Views
2K
Replies
3
Views
7K
  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 5 ·
Replies
5
Views
14K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 14 ·
Replies
14
Views
4K
Replies
5
Views
9K