Mindblown: a blog about philosophy.
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Amplitude, Wavelength, and Frequency
The figure is a history graph at x = 0 m of a wave moving to the right at 2 m/s. What is the amplitude of this wave? A = How high it goes = 6cm What is the frequency of this wave? T = .6 F= 1/.6 = 1.66 = 1.7 Hz =2 Hz What…
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Frequency of Electromagnetic Wave
What is the wavelength of a 2.4 MHz ultrasound wave traveling through aluminum? Assume that the speed of sound in aluminum is 5100 m/s. frequency = 2.4 Mhz = 2400000hz v = 5100 m/s λ = v/f 5100/2400000 = .002125 m = 2.212500 mm What frequency of electromagnetic wave would have the same wavelength as the ultrasound…
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How Many Joules of Solar Energy?
The intensity of electromagnetic waves from the sun is 1.4 KW/m2 just above the earth’s atmosphere. Eighty percent of this reaches the surface at noon on a clear summer day. Suppose you model your back as a 33 cm x 53 cm rectangle. How many joules of solar energy fall on your back as you work on your tan for 1.4 h?…
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What is the Frequency?
A friend of yours is loudly singing a single note at 400 Hz while racing toward you at 25.5 m/s on a day when the speed of sound is 340 m/s. What frequency do you hear? = (346/346-24.6) 380 = 346 x 380/ 321.4 = 409.085 = 409 hz
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What is the Period and Frequency?
In taking your pulse, you count 71 heartbeats in 1 min. What is the period of your heart’s oscillations? Time taken for 71 heart beats = 1 min = 1* 60 seconds =60 s The time taken for 1 heart beat = 60 / 71 Time Period =.85 seconds What is their frequency? frequency f = 1…
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Period, Frequency, Amplitude, and Maximum Speed
1/freqAn air-track glider attached to a spring oscillates between the 15.0 mark and the 55.0 cm mark on the track. The glider completes 15.0 oscillations in 37.0 . What are the (a) period = 1/frequency = 1/.405 = 2.5 seconds (b) frequency = oscillations / time = 15/37= .41 Hz (c) amplitude amplitude = 1/2 of the difference of oscillation marks = 1/2(55-15) = 20cm (d)…
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What is the Spring Constant?
A spring has an unstretched length of 13 cm. When an77 g ball is hung from it, the length increases by 7.0 cm. Then the ball is pulled down another 7.0 cm and released. What is the spring constant of the spring? The force of gravity on the ball = the force on the spring Known Variable: M(mass): 77 g…
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What is the Maximum Acceleration?
Some passengers on an ocean cruise may suffer from motion sickness as the ship rocks back and forth on the waves. At one position on the ship, passengers experience a vertical motion of amplitude 1.4 m with a period of 17 s. What is the maximum acceleration of the passengers during this motion? = (2p / T )2…
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What is the Spring Constant?
A 237 g air-track glider is attached to a spring. The glider is pushed in 8.64 cm against the spring, then released. A student with a stopwatch finds that 14 oscillations take 13.94 s. What is the spring constant? Known variables: mass m = 237 g = 0.237 kg time taken for 14 oscillations…
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Period and Amplitude
A 175 g mass attached to a horizontal spring oscillates at a frequency of 2.0 Hz. At one instant, the mass is at x = 5.0 cm and has vx = -32 cm/s Determine the period. P = 1 / f = 1 / 2.0 T= 0.5 sec. Determine the amplitude. w = 2pi *…
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