- #1

govindsuku

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You should upgrade or use an alternative browser.

In summary: If the torque measured by the dynamometer is too low, you may be missing something in your measurements. You could try to calibrate your dynamometer to some other torque standard, or use a different setup to measure the torque at the wheels.

- #1

govindsuku

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- #2

K^2

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[tex]\omega_1 R_1 = -\omega_2 R_2[/tex]

If slipping does occur, you have a different constraint.

[tex]\frac{\tau_1}{R_1} = -\frac{\tau_2}{R_2} = ±F_f[/tex]

Where F

- #3

govindsuku

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- #4

K^2

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- #5

govindsuku

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- #6

K^2

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Consider, instead, a case where the wheel is driven by an electric motor, whose torque changes with angular velocity roughly like this. (I'm oversimplifying a bit, but it's not a bad model for simple DC motor.)

[tex]\tau = \tau_{max}(\omega_{max} - \omega)[/tex]

Suppose, also, that the torque at ω=0 is such that it causes the wheels to slip. Now the driven wheel spins up quickly until the torque from motor balances torque from friction. This gives time for the second wheel, under friction torque, to catch up with the angular velocity of the former. At that point, the two wheels go back into a no-slipping mode, and keep accelerating together to level off at ω

If you also have load on the second wheel, then things get a little bit more interesting. But this is basically a greatly simplified model of a clutch. (For a real clutch, you also need to consider the flywheel.)

- #7

govindsuku

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- #8

K^2

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Oh, and constant throttle won't give you constant power in this setup. Engine RPM will vary with amount of torque you apply to wheels, and power output depends on throttle position and RPM. The curve relating the two can be quite complex, but essentially, that's what you are measuring.

- #9

govindsuku

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- #10

sophiecentaur

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You seem to have been surprised by the torque involved. What actual power did this involve? Was the Engine working hard at the time (labouring with lots of noise and foot flat down)? Only when that's happening will you be getting the maximum power out of it.

It may be worth checking that you got your ratio of wheel diameters the right way up. (Sorry but it's just possible)

- #11

govindsuku

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Cheers!

The Rolling Problem - Disc on Disc is a classic physics problem that involves two discs rolling on top of each other without slipping. This problem is often used to demonstrate the concept of rotational motion and the relationship between linear and angular velocity.

The key variables in the Rolling Problem - Disc on Disc include the radius of each disc, their masses, and their linear and angular velocities. The coefficient of friction between the two discs and the surface they are rolling on may also be considered.

Rolling without slipping is when the point of contact between the two discs remains fixed and does not slip, while rolling with slipping is when the point of contact moves and slips. In the Rolling Problem - Disc on Disc, the discs are assumed to roll without slipping.

The Rolling Problem - Disc on Disc can be solved using various methods, such as using the conservation of energy or applying torque and angular momentum equations. The specific method used may depend on the given information and the problem's constraints.

The Rolling Problem - Disc on Disc has various real-world applications, including understanding the motion of gears and wheels, analyzing the motion of planets and satellites, and designing vehicles with wheels or rolling components.

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