I have always wondered why the spring constant is measured in Newton metres and not joules. What is the conceptual reasoning behind this? After all, a 1nm^-1 = 1J.
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Well, as others have pointed out, a joule is a newton TIMES a meter, not divided by. Spring constant is newton PER meter. That is, newton divided by meters.
But here is something very similar for you to ponder. Why is it that torque, which *is* newtons times meters cannot be written as joules?
But here is something very similar for you to ponder. Why is it that torque, which *is* newtons times meters cannot be written as joules?
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1 Nm is 1 J ie 1 N * 1 m ( Energy in Joules )
1 N m^-1 = 1 N/m = 1 N / 1m ( spring constant k)
These are absolutely NOT the same thing.
to get from the spring constant to energy we need to multiply by m^2
In fact the energy E = 1/2 k x^2
so the energy is 1/2 * spring constant * square of the extension.
1 N m^-1 = 1 N/m = 1 N / 1m ( spring constant k)
These are absolutely NOT the same thing.
to get from the spring constant to energy we need to multiply by m^2
In fact the energy E = 1/2 k x^2
so the energy is 1/2 * spring constant * square of the extension.
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[k]=N/m=J/m^2
J=N*m=kg*m^2/s^2
Joule is unit for energy, amount of work done by 1N force over 1m distance, do not equal reversed cm or nm.
Newton is unit of force, needed to accelerate 1kg to 1m/s^2.
J=N*m=kg*m^2/s^2
Joule is unit for energy, amount of work done by 1N force over 1m distance, do not equal reversed cm or nm.
Newton is unit of force, needed to accelerate 1kg to 1m/s^2.
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newton meters to the power -1 is the same thing as joules. So there is not much difference after all.