Lecture 5- Pendulums and Dampled SHM Chapter 15.1-15.3

Prof. Noronha-Hostler PHY-124H HONORS ANALYTICAL PHYSICS IB

Phys- 124H Feb. 15th, 2018

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Tutoring

Tutoring for a fee: http://physics.rutgers.edu/descr/tutorpage2017.pdf Math and Science Learning Center: https://rlc.rutgers.edu/services/peer-tutoring

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Test

Exams are graded by GradeBook is having issues, hopefully something by the end of the day...

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Physical Pendulum

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SHM vs. Circular motion

5 / 13 15.4.5. If the mass of a simple pendulum is doubled, how does the frequency of oscillation change, if at all? a) The frequency would double. b) The frequency would be reduced to one-half its initial value. c) The frequency would be reduced by a factor of (2 / 2 ). d) The frequency would increase by a factor of 2. e) The frequency would be unchanged. 15.4.5. If the mass of a simple pendulum is doubled, how does the frequency of oscillation change, if at all? a) The frequency would double. b) The frequency would be reduced to one-half its initial value. c) The frequency would be reduced by a factor of (2 / 2 ). d) The frequency would increase by a factor of 2. e) The frequency would be unchanged. 15.4.8. A grandfather clock, which uses a pendulum to keep accurate time, is adjusted at sea level. The clock is then taken to an altitude of several kilometers. How will the clock behave in its new location? a) The clock will run slow. b) The clock will run fast. c) The clock will run the same as it did at sea level. d) The clock cannot run at such high altitudes. 15.4.8. A grandfather clock, which uses a pendulum to keep accurate time, is adjusted at sea level. The clock is then taken to an altitude of several kilometers. How will the clock behave in its new location? a) The clock will run slow. b) The clock will run fast. c) The clock will run the same as it did at sea level. d) The clock cannot run at such high altitudes. Admin Pendulums Dampening Resonance

Damped oscillator

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Damped oscillator

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Damped oscillator

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Resonance

Bridge resonance

9 / 13 15.5.1. Consider three different torsion pendulums, each of mass m, consisting of a solid disk suspended from the middle of one flat side, a hollow sphere, and a rod suspended from the middle. The diameter of the disk and sphere are both the same as the length of the rod. The wires they are suspended from are identical. Which torsion pendulum will twist back and forth the fastest? a) the disk b) the rod c) the sphere d) The disk and the rod will oscillate with the same frequency. 15.5.1. Consider three different torsion pendulums, each of mass m, consisting of a solid disk suspended from the middle of one flat side, a hollow sphere, and a rod suspended from the middle. The diameter of the disk and sphere are both the same as the length of the rod. The wires they are suspended from are identical. Which torsion pendulum will twist back and forth the fastest? a) the disk b) the rod c) the sphere d) The disk and the rod will oscillate with the same frequency. 15.6.2. At the surface of Mars, the acceleration due to gravity is 3.71 m/s2. On Earth, a pendulum that has a period of one second has a length of 0.248 m. What is the length of a pendulum on Mars that oscillates with a period of one second? a) 0.0940 m b) 0.143 m c) 0.248 m d) 0.296 m e) 0.655 m 15.6.2. At the surface of Mars, the acceleration due to gravity is 3.71 m/s2. On Earth, a pendulum that has a period of one second has a length of 0.248 m. What is the length of a pendulum on Mars that oscillates with a period of one second? a) 0.0940 m b) 0.143 m c) 0.248 m d) 0.296 m e) 0.655 m Admin Pendulums Dampening Resonance

Wave Types

Mechanical Waves

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Waves

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Wave Types

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Wave Types

13 / 13 16.3.1. A transverse wave is traveling along a Slinky. The drawing below represents a section of the Slinky at one instant in time. The direction the wave is traveling is from left to right. Two segments are labeled on the Slinky. At the instant shown, which of the following statements correctly describes the motion of the particles that compose the Slinky in segments A and B?

a) In segment A the particles are moving downward and in segment B the particles are moving upward. b) In segment A the particles are moving upward and in segment B the particles are moving upward. c) In segment A the particles are moving downward and in segment B the particles are moving downward. d) In segment A the particles are moving upward and in segment B the particles are moving downward. e) In segment A the particles are moving toward the left and in segment B the particles are moving toward the right. 16.3.2. Mike is holding one end of a Slinky. His hand moves up and down and causes a transverse wave to travel along the Slinky away from him. Is the motion of Mike’s hand a wave? a) Yes, the motion of Mike’s hand is a wave because it moves up and down in periodic motion. b) Yes, the motion of Mike’s hand is a wave because Mike is transferring energy to the Slinky. c) No, the motion of Mike’s hand is not a wave because there is no traveling disturbance. d) No, the motion of Mike’s hand is not a wave because there is no energy traveling along the Slinky. 16.3.2. Mike is holding one end of a Slinky. His hand moves up and down and causes a transverse wave to travel along the Slinky away from him. Is the motion of Mike’s hand a wave? a) Yes, the motion of Mike’s hand is a wave because it moves up and down in periodic motion. b) Yes, the motion of Mike’s hand is a wave because Mike is transferring energy to the Slinky. c) No, the motion of Mike’s hand is not a wave because there is no traveling disturbance. d) No, the motion of Mike’s hand is not a wave because there is no energy traveling along the Slinky.