Answer:
The amount of C remaining after time t is
Explanation:
We can represent the decay sequence as
The reason we added D is because we are told from the question that C is also radioactive so it has the tendency to decay
Generally for every decay the remaining radioactive element can be obtained as
Where N is the amount of the remaining radioactive material
is the original amount amount of the radioactive material before decay
and is the decay constant
Now for the decay from amount of radioactive element B formed from A after time t can be obtained as
Where is the decay constant of A
Now for the decay from amount of radioactive element C formed from A after time t can be obtained as
Where is the decay constant of B
Now for the decay from amount of radioactive element D formed from A after time t can be obtained as
So this amount of D is the reaming amount of the radioactive material C
Answer:
Explanation:
The complete sequence of motions and activities required to complete one work cycle.
Answer:
The refractive index of the material is 1.28.
Explanation:
It is given that,
Refractive index of medium 1, n₁ = 1.31
Critical angle,
At critical angle rays will reflects at 90 degrees. Using Snell's law as:
At critical angle,
So, the refractive index of the material is 1.28. Hence, this is the required solution.
Answer:
Explanation:
We shall apply Doppler's effect to solve the problem .
Formula for apparent frequency for a source of sound approaching an observer is as follows .
f₁ = f₀ V / (V - v )
where f₁ and f₀ are apparent and real frequency of source , V and v is velocity of sound and velocity of approaching source respectively .
Putting the given values and knowing that speed of sound is 340 m /s
f₁ =346x 340 / (340 - 39.6 )
f₁ = 391.6 Hz
In case of receding train , the formula is
f₂ = f₀ V / (V + v )
Putting the values
f₂ = 346x 340 / (340 + 39.6 )
= 309.9 Hz
Change in frequency = 391.6 - 309.9
= 81.7 Hz .