Relation btw angular acceleration of driveshaft and wheels.

[rpower]

Hello guys
I read yesterday that angular acc at driveshaft is related to angular acceleration at wheels as:
ang acc (d) = ang acc(w) x N
Where N is final drive ratio (differential)
This shows ang acc at drveshaft is greater than wheels and therefore torque because,
Torque = I (MoI) x alpha (ang acc.)
How is this possible? Because diff amplifies the torque input i.e toque output of diff should be greater than input and so should angular acc.

[BigOhm]

You're jumping to an unwarranted conclusion. Consider for a minute a very artificial situation where a driveshaft rotates 4 times for each rotation of the wheel. Don't worry about what the differential is doing - this is a gendanken car. In order to get an acceleration of, say, 2 sec^-2 at the wheel, you must have an acceleration of 8 sec^-2 at the driveshaft.

Now, the torque = I alpha formula is right, but you probably can't use it here since the driveshaft sees "reflected" I from the wheels. Look at this in terms of work and you'll see that, in the above situation, the driveshaft has only 1/4 the torque as the wheel.

[rpower]

So u mean the driveshaft has greater ang acc but it has small moment of inertia as compared to differential gear, so it has less torque. IS it?