An acceleration has a seismic mass of 0.06 kg and a spring constant of 4500 N/m. Maximum mass displacement is + - 0.025 m (before mass hits the top). Determine maximum measurable acceleration and natural frequency.
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1275 m/s; 60 Hz
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1875 Hz; 44 m/s
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1875 m/s; 44 Hz
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4113 m/s; 60 Hz
C
Correct answer
Explanation
Seismic mass = (M) 0.06 kg
Spring constant (K) = 4500 N/m (Natural angular velocity)2 = K/M = 4500/0.06 = 273.86 rad /sec
Maximum mass displacement (A) = 0.025 m
Maximum acceleration = (Natural angular velocity)2 x maximum mass displacement = (273.86)2 x 0.025 = 1875 m/s
Natural Frequency (f0) = Natural angular velocity/2 pi = 44 Hz