- #1
NewtonianAlch
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The way I have understood it is that dynamic torque involves angular acceleration, while static torque has zero angular acceleration:
α =Δω/Δt = 0
But static torque still has centripetal acceleration with constant speed:
ac = v2/r
where v is linear velocity, and r is the radius
Then F = mac = (mv2)/r
Torque = F . r
Therefore static torque τs = ( (mv2)/r ) . r = mv2Let us consider a wheel of mass 10kg powered through a driveshaft connected to the output of an engine/motor, with a linear velocity of 10m/s (36km/h) on a road.
Using the equation above, the static torque at the wheel due to constant speed:
τs = 10.(102) = 1000Nm
1) What is the gap in my understanding? I do not see how a wheel traveling at 10m/s could possibly generate 1000Nm. If we consider freeway speeds: 36m/s (~130km/h). Then the static torque is 12,960Nm.
2) Say we also consider the actual car attached to the wheel which is moving. Do we need to add the mass of the car (1000kg) to the wheel's mass? So at 10m/s:
τs = 1010.(102) = 101,000Nm
I am guessing no! So what gives?
α =Δω/Δt = 0
But static torque still has centripetal acceleration with constant speed:
ac = v2/r
where v is linear velocity, and r is the radius
Then F = mac = (mv2)/r
Torque = F . r
Therefore static torque τs = ( (mv2)/r ) . r = mv2Let us consider a wheel of mass 10kg powered through a driveshaft connected to the output of an engine/motor, with a linear velocity of 10m/s (36km/h) on a road.
Using the equation above, the static torque at the wheel due to constant speed:
τs = 10.(102) = 1000Nm
1) What is the gap in my understanding? I do not see how a wheel traveling at 10m/s could possibly generate 1000Nm. If we consider freeway speeds: 36m/s (~130km/h). Then the static torque is 12,960Nm.
2) Say we also consider the actual car attached to the wheel which is moving. Do we need to add the mass of the car (1000kg) to the wheel's mass? So at 10m/s:
τs = 1010.(102) = 101,000Nm
I am guessing no! So what gives?