A starship blasts past the earth at 2.0*10^8 m/s .Just after passing the earth, the starship fires a laser beam out its back of
1 answer:
Answer:
at the speed of light ()
Explanation:
The second postulate of the theory of the special relativity from Einstein states that:
"The speed of light in free space has the same value c in all inertial frames of reference, where "
This means that it doesn't matter if the observer is moving or not relative to the source of ligth: he will always observe light moving at the same speed, c.
In this problem, we have a starship emitting a laser beam (which is an electromagnetic wave, so it travels at the speed of light). The startship is moving relative to the Earth with a speed of 2.0*10^8 m/s: however, this is irrelevant for the exercise, because according to the postulate we mentioned above, an observer on Earth will observe the laser beam approaching Earth with a speed of .
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Answer:
2 J
Explanation:
A charged capacitor of capacitance with energy of 7.54 J, is connected in parallel with another capacitor
, so the charge is equally distributed between them.
(a) The energy stored in the capacitor before it being connected to the other capacitor is:
The energy stored in the electric field is the sum of the energies of the two capacitors:
since the charge equally distributed, =
=
. and since they are connected in parallel the potential difference on both of them is the same
:
hence,
Answer:
Explanation:
As in any sample you will have 75.8% of Cl-35 iosotopes and 24.3% of Cl-37 iosotopes you can get the average atomic mass as:
Answer:
The speed of nitrogen molecule is 1.87 m/s.
Explanation:
Given that,
Pressure = 2 atm
Density = 1.7 grams/liter
Atomic weight = 28 grams
We need to calculate the temperature
Using formula of idea gas
Put the value into the formula
We need to calculate the speed of nitrogen molecule
Using formula of RMS speed
Hence, The speed of nitrogen molecule is 1.87 m/s.