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A 175 kg boat is floating on the water. A person of 75.0 kg steps into the boat, and the boat sinks by 11.5 cm. When the person gets off the boat, the boat starts to oscillate in SHM. Calculate the effective spring constant and the frequency of the oscillations.

User Guapolo
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The effective spring constant is 6391.3 N/m and the frequency of the oscillations is approximately 0.569 Hz.

To calculate the effective spring constant and frequency of the oscillations, we can use the equation for the period of a mass-spring system:

T = 2π√(m/k)

Step 1: Calculate the effective spring constant (k)

Using the given information, we have:

Initial mass of the boat = 175 kg

Mass of the person = 75.0 kg

Change in displacement = 11.5 cm = 0.115 m

Weight of the person = Mass of the person × Acceleration due to gravity = 75.0 kg × 9.8 m/s² = 735 N

From Hooke's Law, we know that the force exerted by the spring is equal to the weight of the person when displaced:

F = kx, where F is the force, k is the spring constant, and x is the displacement

Thus, k = F/x = 735 N / 0.115 m = 6391.3 N/m

Step 2: Calculate the frequency (f)

Using the formula T = 1/f, where T is the period and f is the frequency, we can rearrange the formula for the period:

T = 2π√(m/k)

1/f = 2π√(m/k)

f = 1/(2π)√(k/m)

Substituting the values, we get:

f = 1/(2π)√(6391.3 N/m / (175 kg + 75.0 kg)) = 1/(2π)√(6391.3 N/m / 250 kg) ≈ 0.569 Hz

Therefore, the effective spring constant is 6391.3 N/m and the frequency of the oscillations is approximately 0.569 Hz.

User Shibli
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