Hmmm. It is easy to calculate the torque needed to stop the wheel in two seconds. Now it seems to be more important to me to stop the bike before it gets to the cliff, which is quite another calculation.
rotationalimmpule=changeinangularMomentum
Torque*time=momnetInertia*changeangularvel
Torque*2=m*r^2*98.7
solve for torque.
Again, this stops the wheel from rotating in 2 seconds...it has little to do with stopping the bike
the wheel might be stopping on the way down, or the wheel might be stopped at the top, but the bike slides over the cliff, due to insufficient frictional force.
You are riding your bike and the tire has a radius of 0.33 m and mass 1.5 kg rotating at 98.7 rad/s. You just notice you are just seconds to riding off a cliff what torque will you need to stop the tire in 2.0 s before you find yourself at the bottom of a 1000 m cliff. New sport extreme mountain bike riding.
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