Answer:
1) f= 8.6 GHz
2) t= 0.2 ms
Explanation:
1)
- Since microwaves are electromagnetic waves, they move at the same speed as the light in vacuum, i.e. 3*10⁸ m/s.
- There exists a fixed relationship between the frequency (f) , the wavelength (λ) and the propagation speed in any wave, as follows:
- Replacing by the givens, and solving for f, we get:
⇒ f = 8.6 Ghz (with two significative figures)
2)
- Assuming that the microwaves travel at a constant speed in a straight line (behaving like rays) , we can apply the definition of average velocity, as follows:
where v= c= speed of light in vacuum = 3*10⁸ m/s
d= distance between mountaintops = 52 km = 52*10³ m
⇒ t = 0.2 ms (with two significative figures)
Answer:
-3+3 i think this is the answer
Explanation:
i think you can ask someone else sorry
Actually, two of the statements can be argued to be true:
1)Changing several different factors in an experiment takes too many controls.
This means that for every factor that is changed you need a control which has all the other factors stable - but with many factors, this might be undoable.
2) - and this is the best answer:
When only one factor is changed, you can be more certain that it caused the results.
If this factor is the only thing that changes, you can safely assume that it caused the results!
Answer:
Explanation:
The PE equation for a mass/spring system is
Δx² and filling in:
and
so
k = 26000 N/m
If the displacement from equilibrium changes more, the PE needed to compress it will also change.
gives us that
PE = 520J
Answer:A and C
Explanation:i got them correct