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stored energy

A load of 800g on a spring produces an extension of 10cm. How much energy is stored in this spring?

How does the formua work??

Reply 1

specialk_698

tryna work out the potential energy of the system (load + spring)

PE = mgh

dont forgert m is in kg and h is in m

Reply 2

sonofdot

energy stored = 1/2 x force x extension
the force is the mass x gravity
you should have everything from here...

Reply 3

0zero0

sonofdot

energy stored = 1/2 x force x extension
the force is the mass x gravity
you should have everything from here...

what unit should i use in the answer?

Reply 4

sonofdot

0zero0

what unit should i use in the answer?

as long as the mass is in kg, and the extension is in m, energy is measured in Joules (J)

Reply 5

Mehh

0zero0

what unit should i use in the answer?

I always find that that question is rather awkward and makes no sense at all.
The units on the LHS must always equal the RHS.
So if you use Newtons and meters on the left hand side, the right hand side would have to be the Newton-Meter. Otherwise known as the Joule.

The best example of this I can think of is in measuring pressure.
Pressure is either measured in Pascals, Pounds per Square Inch or Bars.
The first two are exactly like I say.
Pascals is Newtons / square meter.
PSI is well...Pounds / square Inch.

This is the basis for a concept called Dimensional Analysis.