50. A baby bounces up and down in her crib. Her mass is 12.5 kg, and the crib mattress can be modeled as a light spring with force constant 700 N/m. (a) The baby soon learns to bounce with maximum amplitude and mini- mum effort by bending her knees at what frequency? (b) If she were to use the mattress as a trampoline- losing contact with it for part of each cycle-what mini- mum amplitude of oscillation does she require?

50. A baby bounces up and down in her crib. Her mass is 12.5 kg, and the crib mattress can be modeled as a light spring with force constant 700 N/m. (a) The baby soon learns to bounce with maximum amplitude and mini- mum effort by bending her knees at what frequency? (b) If she were to use the mattress as a trampoline- losing contact with it for part of each cycle-what mini- mum amplitude of oscillation does she require?

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter12: Oscillatory Motion

Section: Chapter Questions

Problem 17P: A block of unknown mass is attached to a spring with a spring constant of 6.50 N/m and undergoes...

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A 2.00-kg block hangs without vibrating at the end of a spring (k = 500. N/m) that is attached to the ceiling of an elevator car. The car is rising with an upward acceleration of g/3 when the acceleration suddenly ceases (at t = 0). (a) What is the angular frequency of oscillation of the block after the acceleration ceases? (b) By what amount is the spring stretched during the time that the elevator car is accelerating?
A 2.00-kg block hangs without vibrating at the end of a spring (k = 500. N/m) that is attached to the ceiling of an elevator car. The car is rising with an upward acceleration of g/3 when the acceleration suddenly ceases (at t = 0). (a) What is the angular frequency of oscillation of the block after the acceleration ceases? (b) By what amount is the spring stretched during the time that the elevator car is accelerating?
A block of unknown mass is attached to a spring with a spring constant of 6.50 N/m and undergoes simple harmonic motion with an amplitude of 10.0 cm. When the block is halfway between its equilibrium position and the end point, its speed is measured to be 30.0 cm/s. Calculate (a) the mass of the block, (b) the period of the motion, and (c) the maximum acceleration of the block.
A mass-spring system moves with simple harmonic motion along the x axis between turning points at x1 = 20 cm and x2 = 60 cm. For parts (i) through (iii), choose from the same five possibilities, (i) At which position does the particle have the greatest magnitude of momentum? (a) 20 cm (b) 30cm (c) 40 cm (d) some other position (e) The greatest value occurs at multiple points, (ii) At which position does the particle have greatest kinetic energy? (iii) At which position does the particle-spring system have the greatest total energy?
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