Answer:
7. 1.56
8. A curved line that slopes upward
Explanation:
7. The curve for quartz at the left side of the graph (400 nm) is just above the middle of the distance between 1.5 and 1.6, so is best approximated by 1.56.
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8. The graph shows n vs. wavelength. The question asks about n vs. frequency. Frequency is inversely proportional to wavelengh, which means you need to describe the curve from right to left, rather than left to right. From right to left, the curve rises, so can be called "a curved line that slopes upward."
Answer:
the second law of thermodynamics. that some energy is destroyed in every energy conversion.
Explanation:
According to the second law of thermodynamics, energy conversion is never 100% efficient. Some energy is always lost as it is being converted from one form to the other.
The fact that a steer must eat at least 100 pounds of grain to gain less than 10 pounds of muscle tissue shows that not all the energy taken up from the grain is channelled towards building the muscle tissue. Some energy from the grains are lost on the way according to the second law of thermodynamics.
Here's a formula that's simple and useful, and if you're really in
high school physics, I'd be surprised if you haven't see it before.
This one is so simple and useful that I'd suggest memorizing it,
so it's always in your toolbox.
This formula tells how far an object travels in how much time,
when it's accelerating:
Distance = (1/2 acceleration) x (Time²).
D = 1/2 A T²
For your student who dropped an object out of the window,
Distance = 19.6 m
Acceleration = gravity = 9.8 m/s²
D = 1/2 G T²
19.6 = 4.9 T²
Divide each side by 4.9 : 4 = T²
Square root each side: 2 = T
When an object is dropped in Earth gravity,
it takes 2 seconds to fall the first 19.6 meters.