Understanding Gear Ratios: Inputs vs Reality

[961008]

The gear ratio is the ratio of angular displacement, angular velocity, angular acceleration, torque etc of the input with respect to output. However, I would like to know that which of these variables will be scaled exactly to the gear ratio in reality, as there might be some friction in the gear, or any other uncertainties in reality. So, which of these will be affected?

 

[billy_joule]

All will be affected by some degree via backlash, strain and friction. In most cases strain and backlash are ignored so velocities and accelerations are proportional. Friction is much less often ignored.

 

[CWatters]

The ratio the usually matches "in reality" is the rpm. That's because gears don't slip.

 

[OldYat47]

All but the torque. Input torque will be greater than output torque due to friction. Angular displacement, angular velocity, angular acceleration all scale exactly to gear ratios.