Torque Question airplane wheels

AI Thread Summary
An airliner lands at 45.0 m/s, with each wheel having a radius of 1.25 m and a moment of inertia of 110 kg·m². The wheels begin to spin due to friction as they touch down, supporting a weight of 1.40 x 10^4 N and achieving rolling without slipping in 0.53 seconds. The angular velocity was calculated to be 36 rad/s, with an angular acceleration of 67.925 rad/s². The discussion highlights confusion about applying the correct equations, particularly regarding the role of friction on multiple wheels and the relationship between linear and angular acceleration. Understanding the rotational dynamics and friction's impact is crucial for solving the problem effectively.
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1. An airliner lands with a speed of 45.0 m/s. Each wheel of the plane has a radius of 1.25 m and a moment of inertia of 110 kg·m2. At touchdown the wheels begin to spin under the action of friction. Each wheel supports a weight of 1.40 x 10^4 N, and the wheels attain the angular speed of rolling without slipping in 0.53 s. What is the coefficient of kinetic friction between the wheels and the runway? Assume that the speed of the plane is constant.



2. Homework Equations :
v=rw
I= 2/5MR^2
F=ma
friction=un
sum of forces?



3. I started by finding the angular velocity. using v=rw, i found it to be 36 rad/s. Then, I found the angular acceleration by doing w=w+at and a is equal to 67.925 rad/s^2. I don't know what to do next? Should I do the F=ma? But a is the linear acceleration and I don't know. I'm really confused about this problem because friction acts on four wheels or something? I don't know. Help please?
 
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The rotational version of F=ma is T=W*ar where ar is rotational acceleration, W is the moment of inertia, and T is the torque
 
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