mlm1234
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During engineering class we where doing dimenison analysis

but im not sure if she taught us wrong
she said work done = force x velocity
work done M^1L^2T^-3
and power = work done / time or torque x angular velocity
power = M^1 L^2 T^4

i have to had in work monday not sure
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Eimmanuel
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(Original post by mlm1234)
During engineering class we where doing dimenison analysis

but im not sure if she taught us wrong
she said work done = force x velocity
work done M^1L^2T^-3
and power = work done / time or torque x angular velocity
power = M^1 L^2 T^4

i have to had in work monday not sure

Indeed, you are taught of the wrong stuff.
Work done = Force × Displacement
So the dimension of work done is
M L2 T-2



Power = work done / time taken
So the dimension of power is
M L2 T-3

In rotational dynamics, you can show that power = torque × angular velocity
https://en.wikipedia.org/wiki/Torque...er,_and_energy
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mlm1234
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In rotational dynamics, you can show that power = torque × angular velocity
https://en.wikipedia.org/wiki/Torque...er,_and_energy[/QUOTE]

with the torque
do you use angular acceleration/ velocity to calulacate the later equation of torque or linear veolcity/acceleration
teach not that good
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Eimmanuel
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(Original post by mlm1234)
In rotational dynamics, you can show that power = torque × angular velocity
https://en.wikipedia.org/wiki/Torque...er,_and_energy

with the torque
do you use angular acceleration/ velocity to calulacate the later equation of torque or linear veolcity/acceleration
teach not that good
I don't know understand what you are asking.
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mlm1234
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(Original post by Eimmanuel)
I don't know understand what you are asking.
When calculating the torque
do i use the angular velocity i calulated or linear volciety
force x displacement = torque
mass x accesleration = acceleration
velocity / t = acceleration

do i calulate the angular velocity and use that to get to torgue
or use the linear

displacement / time / radius = angular velocity


then apply it to the power = torque x angular velocity
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Eimmanuel
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(Original post by mlm1234)
When calculating the torque
do i use the angular velocity i calulated or linear volciety
force x displacement = torque
mass x accesleration = acceleration
velocity / t = acceleration

do i calulate the angular velocity and use that to get to torgue
or use the linear

displacement / time / radius = angular velocity


then apply it to the power = torque x angular velocity
If you are asking for general rule or fixed rule, I doubt that you can find one. It depends on the problem.
https://cnx.org/contents/[email protected]

It seems that you don't understand torque based on what you are writing. Torque or moment of force does not depend on displacement and note that it is a vector.
https://www.physics.uoguelph.ca/tuto...que.intro.html
https://en.wikipedia.org/wiki/Torque

In physics or engineering, it is usually written as
  \vec{\tau} = \vec{r} \times \vec{F}

 \vec{r} is NOT displacement. It is usually known as perpendicular distance from a pivot or moment arm in A level physics.

Calculating power using torque and angular velocity is a scalar triple product.
https://en.wikipedia.org/wiki/Triple_product
https://mathinsight.org/scalar_triple_product

 P = \vec{\tau} \cdot \omega = (\vec{r} \times \vec{F}) \cdot \omega
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