Question #a7964

1 Answer
Oct 12, 2014

"When a force acts upon an object to cause a displacement of the object, it is said that work was done upon the object. There are three key ingredients to work: force, displacement, and cause. In order for a force to qualify as having done work on an object, there must be a displacement and the force must cause the displacement." Source:http://www.physicsclassroom.com/class/energy/Lesson-1/Definition-and-Mathematics-of-Work

The work equation is #"W"# = #"F"# x #d#, where W is work in Joules (J), F is force in N or #"kg*m/s"^2#, and #d# is displacement. A Joule is a #"kg*m"^2/"s"^2#.

Known/Given:
Force, #"F"# = #"137N"#
Work, #"W"# = #"223J"#

Unknown:
displacement, #d#

Equation:
#"W"# = #"F"# x #d#

Solution: To solve for displacement, the work equation will have to be rearranged, so the #d# = #"W"/"F"#. Then plug in your values.

#d# = #"W"/"F"# = #"223J"/"137N"# = #"223kg*m"^2/"s"^2##-: # #"137kg*m"/"s"^2# = #"1.63m"# upward

When dividing a fraction by another fraction, you invert the second fraction and then multiply.

#d# = #"W"/"F"# = #"223J"/"137N"# = #"223kg*m"^2/"s"^2# x #"s"^2/ "137kg*m"# = #"1.63m"# upward

(The #"s"^2# cancels, the #"kg"#cancels, and the #"m"^2/"m"# reduces to #"m"#.)