Recent content by gigli

Homework Statement Two shortwave radio antennas broadcast identical, in-phase signals at the same frequency. The transmitters are 176.0 m north, and 176.0 m south of Western Ave, respectively, as shown (that is, they are separated by 352.0 m). Western Ave is 452.0 m long. Starting at the end...

Got it. Speed of light in plastic. Roger. Appreciate it

How do I determine the speed of light inside the plastic? And I posted a diagram: https://www.physicsforums.com/attachment.php?attachmentid=15094&stc=1&d=1219187822

Homework Statement A light ray enters the plastic block in the illustration at an angle of 33.0° and then exits the opposite side. The long side of the block has a length of 0.670 m and its index of refraction is 1.70. For how much time is the light ray inside the block...

That last little bit really clarified what I was looking for. Thanks for the help Doc Al. Guess I'll try and get cracking on another stumper.

Ooooooooooooooooh. I got it now. Thank you so much. The light was shining a cone straight up, but past 48 degrees it was reflecting back into the water. I was thinking it was a laser beam aimed at 48 degrees. Thanks again! I got the right answer

Yes. When the angle is not quite to the critical angle it shines out of the water. when it reaches the critical angle it shines across the surface of the water, but none shines into the air, and when it is past the critical angle no light shines out of the water only deeper back into the water...

Wouldn't the radius of light only be a point at the surface if it is only a point at the bottom? I'm afraid I'm still not grasping this.

[Solved] Total internal reflection, underwater light? Homework Statement A point source of light is at the bottom of a koi pond, at a depth of 0.525 meters. What is the radius of the circle of light formed on the water's surface? Take the index of refraction of water to be 1.33. Hint: Some of...

I am still having trouble solving this one. Anyone have any advice?

Homework Statement Three parallel wires are arranged in a partial square configuration with point P as the fourth corner. In two of the wires at opposite corners of the square, a 5.00×10^-4 A current flows toward you, and in the third wire opposite the point P, a 7.50×10−4 A current flows away...