Answer and Explanation:
You don't have water because of two possible reasons:
- Because of the summer and the little rain, the underwater supply goes low.
- The slope in the hill you live makes the underground water goes down by the effect of gravity. Imagine the underground water like a small tank, when the water is reduced for any reason the bottom of the tank will have the remaining water, while the top part will be "empty".
Light that enters the new medium <em>perpendicular to the surface</em> keeps sailing straight through the new medium unrefracted (in the same direction).
Perpendicular to the surface is the "normal" to the surface. So the angle of incidence (angle between the laser and the normal) is zero, and the law of refraction (just like the law of reflection) predicts an angle of zero between the normal and the refracted (or the reflected) beam.
Moral of the story: If you want your laser to keep going in the same direction after it enters the water, or to bounce back in the same direction it came from when it hits the mirror, then shoot it <em>straight on</em> to the surface, perpendicular to it.
Answer:
Yes
Explanation:
The core of an electromagnet serves to stabilize the magnetic field created by the wire. The thicker the core, the more metal there is to amplify the current. Therefore, a thicker core does make an electromagnet stronger. Hope this helps!