# Search results

1. ### Relativistic Time for spaceship movement

Ah, I see. I was confused about the wording, because I thought "proper time" (t0) was the time measured by the person on earth, but "proper time" is actually the time that is measured by the person that is moving on the spaceship. Thank you so much for your help!
2. ### Relativistic Time for spaceship movement

I did know that relativistic time (where observer is moving) should be shorter than proper time (where observer is stationary), but our professor gave us this: proper time = t0 relativistic time = t relativistic time = t0 / sqrt[1 - (v/c)^2], which doesn't give the right relationship.... so I...
3. ### Relativistic Time for spaceship movement

Good to know. Our professor gave us the wrong equation in notes. Thanks for your help!
4. ### Relativistic Time for spaceship movement

1. Homework Statement A certain star is 76.6 light-years away. How many years would it take a spacecraft traveling 0.946c to reach that star from Earth, as measured by observers on Earth? How many years would it take to reach that star from Earth, as measured by observers on the spacecraft...
5. ### Infared WAvelengths in transition through energy levels

Ah, I see. I thought that the infared rays were only the ones that landed on level 3, but they can land on level 3, 4, OR 5? However, visible rays ONLY land on level 2 and UV rays ONLY land on level 1, is that correct? Thanks for your help!
6. ### Infared WAvelengths in transition through energy levels

1. Homework Statement How many transitions involving the hydrogen energy levels shown correspond to photons of infrared light? The infrared range is less than 1.8 eV 2. Homework Equations Paschen Lines = Infared wavelengths 3. The Attempt at a Solution I thought that since...
7. ### Destructive Interference when walking toward an antenna

1. Homework Statement Two antennas located at points A and B are broadcasting radio waves of frequency 96.0 MHz, perfectly in phase with each other. The two antennas are separated by a distance d=12.40m. An observer, P, is located on the x axis, a distance x=55.0m from antenna A, so that APB...
8. ### Phase Difference between two waves from antennas

So I know the difference in the paths is 1.4m, but when I multiply that by the wavelength, (3.125m), and convert to radians it is wrong.
9. ### Phase Difference between two waves from antennas

I know that AP = 55m and BP = 56.4m, I just don't know how to find the wavelength of pathlength difference
10. ### Phase Difference between two waves from antennas

1. Homework Statement Two antennas located at points A and B are broadcasting radio waves of frequency 96.0 MHz, perfectly in phase with each other. The two antennas are separated by a distance d=12.40m. An observer, P, is located on the x axis, a distance x=55.0m from antenna A, so that APB...
11. ### Pathlength Difference from two waves

Ah, just figured it out...you have to use "m" and multiply it by the wavelength.
12. ### Pathlength Difference from two waves

So....I think I just realized that pathlength difference refers to "m", but what are the units??
13. ### Pathlength Difference from two waves

1. Homework Statement Two slits separated by a distance of d = 0.12mm are located at a distance of D = 780mm from a screen. The screen is oriented parallel to the plane of the slits. The slits are illuminated by a coherent light source with a wavelength of lambda = 549E-6 mm. The interference...
14. ### Speed of a 796eV electron

Nevermind, I got it myself. I was using the wrong value to convert eV. Thanks anyway
15. ### Speed of a 796eV electron

I didn't ignore it, I don't understand where my units are wrong. eV, m = kg If you would tell me which part I'm doing wrong I could try and fix it.
16. ### Speed of a 796eV electron

I'm using m = 9.11E-31 eV = 796 796 = 1/2*9.11E-31 v^2 796 = 4.55E-31 v^2 1.748E33 = v^2 v = 4.18E16 Don't know where I'm wrong...
17. ### Speed of a 796eV electron

eV = 1/2 mv^2 eV / (1/2m) = v^2 v = sqrt (eV / 1/2m) Am I doing this wrong?
18. ### Speed of a 796eV electron

For: 796 = 1/2 * mv^2 (where m = 9.11E-31) I keep getting 4.18E16 for v I don't understand what part I'm doing wrong, I've done it about ten times...
19. ### Speed of a 796eV electron

I tried converting eV to joules, which gave me 1.27E-16 joules, which gave me 8.36E6 m/s but that is wrong too. I think the units for mass (kg) are correct, I'm not sure what I have wrong...
20. ### Speed of a 796eV electron

If 796 = 1/2 * 9.11E-31 * v^2, I get v to be 4.18E16 m/s which is wrong...i'm not sure what i'm doing wrong...
21. ### Speed of a 796eV electron

1. Homework Statement What is the speed of a 796eV electron? 2. Homework Equations E = hc/lambda E = hv 3. The Attempt at a Solution I'm not sure how to get a value for meters... I know if I take h (plank's constant) and divide the electron, I will get 4.14E-15 ev*s / 796 eV =...
22. ### Real Object, Images formed by a single converging or diverging lens

I didn't know that all virtual images are upright, that is good to know! However, if Part F is true, I still have something else wrong, as I tried: TFTFTT So I'm not sure what other one I have wrong...
23. ### Real Object, Images formed by a single converging or diverging lens

I guess my prof said that a diverging lens could possibly form an inverted image, although I'm not sure how. I also already tried that combination: TFTFTT So I must either have another one wrong or something.... not sure...
24. ### Real Object, Images formed by a single converging or diverging lens

1. Homework Statement Starting with a real object, which of the following statements are TRUE about the image formed by a single lens? (Choose ALL correct answers, e.g. B, AC, CDF.) A) For a converging lens an object has to be placed between the focal length and the lens in order to form a...
25. ### Angle of Incidence with partial reflection and partial refraction

right. i'm an idiot. thanks for your help!
26. ### Angle of Incidence with partial reflection and partial refraction

yep, i'm awful at trig so that isn't surprising. haha. i'm still not getting it right though: if i use that identity, i get: 1 * 2 sin theta cos theta = 1.51 * sin theta If I divide the left by sin theta, the sin theta cancels out (right???), leaving me: 2 cos theta = 1.51 which gives me a...
27. ### Angle of Incidence with partial reflection and partial refraction

1. Homework Statement A beam of light in air strikes a piece of glass (n=1.51) and is partially reflected and partially refracted. Find the angle of incidence if the angle of reflection is twice the angle of refraction. 2. Homework Equations n1sintheta1 = n2sintheta2 3. The...
28. ### Index of Refraction and actual location of fish in water

I went through it a couple times and got the same thing. Thanks so much for your help!!!
29. ### Solving for a variable when the square root of a formula is in the denominator

I get (n^2*x^2) / (x^2 + h^2) = d^2 / (d^2 + h^2) ]
30. ### Index of Refraction and actual location of fish in water

when I try to solve that, I get: x = (h^2 + d^2 + h^2n^2) / n^2 or x = (h + d + hn) / n