Answer Checking: Unit 1 Waves Chapter 1

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The discussion focuses on wave properties, including amplitude, wavelength, speed, and frequency calculations. The amplitude measures the distance from the equilibrium point to the wave's crest or trough, while the wavelength is the distance between successive wave points. Calculations reveal that a wave traveling 4.8m in 6s has a speed of 0.8m/s and a frequency of 0.5Hz, with a wavelength of 1.6m. Differences between transverse and longitudinal waves are noted, emphasizing their respective vibration directions. The conversation concludes with a calculation of the period and frequency of a pendulum, confirming the time required for multiple cycles.
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1. I'll just post the entire question list for this chapter in image format.

http://imgur.com/retjkzJ1.
i) The amplitude is the measurement of the wave from the equilibrium point to the trough or crest of a wave. The wavelength is the measurement of two successive points of a wave.

ii) There are three cycles in this wave. Three cycles have traveled a total of 4.8m. Therefore:
λ=4.8/3
λ=1.6m
The wavelength is 1.6m

iii)The time for the wave to travel 4.8m is 6s.
Speed Equation: Δd/Δt=v
4.8m/6s=0.8m/s
The wave's speed is 0.8m/s
Finding Frequency
v=λ*ƒ
0.8m/s=1.6m*ƒ
0.8m/s/1.6m=ƒ
ƒ=0.5Hz
The frequency is 0.5Hz.

iv) Speed remains the same because the wave is traveling the same distance over the same amount of time (4.8m over 6s).
Speed is 0.8m/s
Finding the wavelength: We know frequency is now 2Hz.
v=λ*ƒ
0.8m/s=λ*2Hz
0.8m/s/2Hz=λ
λ=-0.4m
The wavelength is 0.4m.
The higher the energy, the larger the frequency and the shorter the wavelength.

2) Differences:
Transverse waves have perpendicular vibration to the direction of the wave. Longitudinal waves have parallel vibration to the direction of the wave. They both have wavelength, amplitude and frequency.

The wavelength is the measurement between two successive points of a wave. The amplitude is the measurement of a wave from the equilibrium point to the trough or a crest of a wave. They both refer to properties of a wave.

The period is the time for a wave to complete one cycle. The frequency is how often particles vibrate when a wave passes through the medium. The two equations are complimentary:
ƒ=1/T, T=1/ƒ3)http://imgur.com/4zkNzqn4) 16 cycles in 8s.
T=Δt/N
T=8/16
T=.5s
The period is .5s
ƒ=1/T
ƒ=1/.5s
ƒ=2Hz
The frequency is 2Hz
How long would it take the pendulum to complete 5 cycles?
1 cycle=.5s
0.5s*5=2.5s
It would take the pendulum 2.5s to complete 5 cycles.
 
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For the most part it looks good, but I'm not so sure about your definition of frequency in #2 part iii, or however you want to label it.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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