Recent content by Engineergirl2

  1. E

    Special Relativity Energy Problem a little confused

    Homework Statement At Earth's location, the intensity of sunlight is 1.5kW/m^2. if no energy escaped earth, by how much would Earth's mass increase in 1 day? Homework Equations ΔE=Δmc^2+ΔKE Rearth=6.378x10^3 The Attempt at a Solution I know that the change in kinetic energy does...
  2. E

    Calculating Light Signal Velocity: Relativistic Effects at 0.5c

    Would I use the speed of light for the hypotenuse of my triangle, since it says I'm firing a light signal, and then use simple trig, i.e. Csin60=y for my y-component? I'm really unsure.
  3. E

    Calculating Light Signal Velocity: Relativistic Effects at 0.5c

    Homework Statement You fire a light signal at 60° north of west. (a) find the velocity components of this signal according to an observer moving eastward relative to you at 0.5c. From them, determine the magnitude and direction of light signal's velocity according to the other observer. (b)...
  4. E

    The Doppler Effect of light

    Homework Statement The light from galaxy NGC 221 consists of a recognizable spectrum of wavelengths. However, all are shifted to the shorter wavelength end of the spectrum. In Particular, the calcium "line" ordinarily observed at 396.85nm is observed at 396.58nm. (a) is this galaxy moving...
  5. E

    A Twin Paradox Question, totally lost.

    B/c 24cyrs/0.6c is equal to forty. Therefore you add them and get 60. Then, Anna is 52 years because the total distance that she appears to travel is 19.2? And 19.2cyrs/0.6c is equal to 32. add that to20 and you get 52. I ended up using length contraction. Sorry that was actually pretty easy!
  6. E

    A Twin Paradox Question, totally lost.

    Homework Statement Planet W is 12ly from earth. Anna and Bob are both 20 years old. Anna travels to planet W at 0.6c, quickly turns around, and returns to Earth at 0.6c. How old will Anna and Bob be when Anna gets back? Homework Equations The Attempt at a Solution I've tried...
Back
Top