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A wagon wheel is constructed as such: eight spokes each have a mass of 0.280kg and are 0.3m long. The outer rim has a mass of 1.4kg. A small 10g mass is attached by a string of negligible mass.

a) What is the moment of inertia of the wheel about an axis through its center and perpendicular to the plane of the wheel?
b) The 10g mass is released from rest, what is the torque on the wheel?
c) What is the angular acceleration of the wheel?

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Final answer:

The problem involves calculating the moment of inertia of a wagon wheel, the torque on the wheel due to a hanging mass, and the angular acceleration of the wheel.

Step-by-step explanation:

The problem relates to calculating the moment of inertia and subsequent dynamics of a rotating body which, in this case, is a wagon wheel.

Calculating Moment of Inertia

To calculate the moment of inertia (I) of the wagon wheel about its center, we would use the formula for a rod (spoke) rotating around one end, which is I = (1/3)mr², and the formula for a hoop (outer rim), which is I = mr². With eight spokes and one rim, the total moment of inertia is I = 8 * (1/3)m₀r₀² + m₁r₁², where m₀ and r₀ are the mass and length of a spoke, and m₁ and r₁ are the mass and radius of the rim.

Calculating Torque

To calculate the torque (τ) on the wheel caused by the 10g mass we use the formula torque τ = r * F, where r is the radius to which the mass is attached and F is the force due to gravity on the mass (F = mg, with m being the mass and g is acceleration due to gravity).

Calculating Angular Acceleration

Knowing the torque, we can calculate the angular acceleration (α) using Newton's second law for rotation τ = Iα. Solving this equation for α gives us α = τ/I.

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