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)
It is very interesting step about Relative velocity. Actually, when you'll see the speed of fly in relation to ground, then it's speed would be 65 mph as train is traveling by that speed but if a person in on Train, then fly is at rest for him
Hope this helps!
Answer:
2940.1 joules would you burn in climbing stairs all day.
Explanation:
Work = W = F d
going up stairs would be against force of gravity
W = mgh
where h is the height
the question is not complete because we need speed or distance
h = v t
so assuming 1 step per second
h = 86,400 steps 7inchs/step 0.0254 m/inch
h = 15362 m
so from this
W = 800 N 15362
= 12289600 J
that means YOU need 12289600 J to walk 1 step per second all day
divide that by 4180 J /Kcal
Kcal =
=
= 2940.1 Kcal
if you ran faster you would use more energy 2 steps per second would mean 5880 Kcal.
Answer:
The person will travel 24 meters.
Explanation:
Distance = Rate * TIme
Distance = d = ?
Rate = r = 6 m/s
Time = t = 4 seconds
d = r*t = (6 m/s)*(4 seconds)
d = 24 m
**Note that the units (m/s) and (s/1) cancel to leave the answer in meters, the desired unit**