Turkey On a Spit

This year for thanksgiving my family decided to cook our turkey on a spit.  This was a great opportunity for me to apply my physics knowledge to the real world. I was interested in the amount of force that was required to rotate the turkey once from rest. Each rotation took 5 seconds.

• w=2πf
• f=1rot/5s
• w=1.3rad/s
• wf=wo+ αt
• 1.3rad/s= 0+ α5s
• α=0.26 rad/(s^2)

• Στ= αI
• Assuming a turkey's moment of inertia is equal to that of a solid cylinder
• I=(.5)mr^2
• I=(.5)(6.8kg)(0.22m)^2
• I=0.16kgm^2
• Στ= (0.26rad/(s^2))(0.16kgm^2)
• τ=0.0416Nm (Since there is only one torque at work, this is the torque of the force applied by the person)
• τ=rFsinθ
• 0.0416Nm=(0.15m)Fsin90
• F=0.28N

It only took .28N to rotate the turkey once! That's less than 0.07lbs of force.