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The singapore flyer is a giant observation wheel (similar to a ferris wheel) that has 28 capsules and can hold a total of 784 passengers. the diameter of the wheel is 150 m and the entire thing rotates one complete revolution in 30 m. the rim weighs 7 x 105 , the capsules each weigh 1 x 104 , and the average person weighs 70 . calculate (a) the magnitude of the angular momentum at full capacity, and (b) the average net external torque applied to the spindle (axle) if it comes to a complete stop in 15 m. write your answers using 3 significant digits.

User Fraber
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Final answer:

The magnitude of the angular momentum at full capacity of the Singapore Flyer is 164.04 x 10^5 kg*m^2/s. The average net external torque applied to the spindle (axle) when the Singapore Flyer comes to a complete stop in 15 min is 172.0425 x 10^5 kg*m^2/s^2.

Step-by-step explanation:

To calculate the magnitude of the angular momentum at full capacity, we need to find the total moment of inertia of the Singapore Flyer. The moment of inertia, I, for a wheel with mass m and radius r is given by the equation:

I = 0.5 * m * r^2

Since the wheel consists of 28 capsules, each weighing 1 x 10^4 kg, the total mass of the capsules is m = 28 * 1 x 10^4 kg = 2.8 x 10^5 kg. The radius of the wheel, r, is half the diameter, so it is r = 150 m / 2 = 75 m. Plugging in these values into the moment of inertia equation, we get:

I = 0.5 * 2.8 x 10^5 kg * (75 m)^2 = 787.5 x 10^5 kg*m^2

The magnitude of the angular momentum, L, is given by the equation:

L = I * ω

where ω is the angular velocity. The entire Singapore Flyer rotates one complete revolution in 30 min, which is equal to 2π rad. So the angular velocity, ω, is:

ω = 2π rad / 30 min = 0.209 rad/s

Plugging in the values of I and ω, we get:

L = (787.5 x 10^5 kg*m^2) * (0.209 rad/s) = 164.04 x 10^5 kg*m^2/s

Therefore, the magnitude of the angular momentum at full capacity of the Singapore Flyer is 164.04 x 10^5 kg*m^2/s.

To calculate the average net external torque applied to the spindle (axle) when the Singapore Flyer comes to a complete stop in 15 min, we can use the equation:

τ = I * α

where α is the angular acceleration. The Singapore Flyer rotates one complete revolution in 30 min, which is equal to 2π rad. So the angular acceleration, α, is:

α = 2π rad / (30 min * 60 s/min) = 0.0219 rad/s^2

Plugging in the value of I and α, we get:

τ = (787.5 x 10^5 kg*m^2) * (0.0219 rad/s^2) = 172.0425 x 10^5 kg*m^2/s^2

Therefore, the average net external torque applied to the spindle when the Singapore Flyer comes to a complete stop in 15 min is 172.0425 x 10^5 kg*m^2/s^2.

User Taj Morton
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