Question #5304e

2 Answers
GM_Phrostbyte
Jan 25, 2018

#3.57# meters

Explanation:

#E_P=mgh#

Where #E_P# is the potential energy
#m# is mass in kilograms
#g# is the acceleration of gravity on Earth
#h# is the height above ground (reference point)

Using the units given, you can identify that you have the mass and potential energy, and need height. Plug these numbers into the formula.

#70J=2kg*9.8m/s^2*h#

Simplifying the right-hand side gives #70J=19.6(kg*m)/s^2*h#

Divide both sides by 19.6 kilograms meters per second squared on both sides of the equation to get the height.

#3.57m=h#

LM
Jan 25, 2018

#3.57m# (or #3.5m#)

Explanation:

#GPE = mgh#

where #m# is mass, in #kg#
#g# is gravitational field strength, in #N//kg#
#h# is height, in #m#.

#h = (GPE)/(mg)#

#m = 2kg#
#g ~~ 9.81# (assuming that the question is set on Earth)
#GPE = 70J#

#(GPE)/(mg) = 70/(2*9.81)#

#=70/19.62#

#h = 70/19.62#

#= 3.57m# (3s.f.)

note: if you want to use #10N//kg# for the value of #g#, the method is the same. the answer obtained is #7/2#, which is #3.5m#.

Related questions
Impact of this question
1112 views around the world
You can reuse this answer
Creative Commons License