Physics, 09.05.2020 22:57 jholland03
A 0.250kg mass book falls from the second floor window. During the fall the book opens, so the friction with the air increases. After a 7.0 m fall, it hits the ground at 7.5 m / s.
What is the average value of the friction force?
Answers: 1
Physics, 22.06.2019 12:30
Hydrogen atoms are excited by a laser to the =4n=4 state and then allowed to emit. what is the maximum number of distinct emission spectral lines (lines of different wavelengths) that can be observed from this system? 8 6 2 7 4 5 1 3 calculate the wavelength of the 4⟶14⟶1 transition. =λ=
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Physics, 22.06.2019 13:10
The atoms in a nickel crystal vibrate as harmonic oscillators with an angular frequency of 2.3 × 1013 rad/s. the mass of a nickel atom is 9.75 × 10-26 kg. what is the difference in energy between adjacent vibrational energy levels of nickel? (h = 6.626 × 10-34 j • s, , 1 ev = 1.60 × 10-19 j)
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Physics, 22.06.2019 14:20
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Physics, 22.06.2019 15:50
An object with initial temperature 130 ∘ f is submerged in large tank of water whose temperature is 50 ∘ f . find a formula for f ( t ) , the temperature of the object after t minutes, if the cooling constant is k = − 0.2 . remember newton's law of cooling (the rate of change of temperature with respect to time is equal to k times the difference between the temperature of the object and the surrounding temperature) ! : )
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A 0.250kg mass book falls from the second floor window. During the fall the book opens, so the frict...
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