Answer:
525 Bq
Explanation:
The decay rate is directly proportional to the amount of radioisotope, so we can use the half-life equation:
A = A₀ (½)^(t / T)
A is the final amount
A₀ is the initial amount,
t is the time,
T is the half life
A = (8400 Bq) (½)^(18.0 min / 4.50 min)
A = (8400 Bq) (½)^4
A = (8400 Bq) (1/16)
A = 525 Bq
Answer:
6.003×10¯⁶ N
Explanation:
We'll begin by converting 1 cm to m. This can be obtained as follow:
100 cm = 1 m
Therefore,
1 cm = 1 cm × 1 m / 100 cm
1 cm = 0.01 m
Finally, we shall determine the gravitational attraction. This can be obtained as follow:
Mass 1 (M₁) = 3 Kg
Mass 2 (M₂) = 3 Kg
Distance apart (r) = 0.01 m
Gravitational constant (G) = 6.67×10¯¹¹ Nm²/Kg²
Force of attraction (F) =?
F = GM₁M₂ / r²
F = 6.67×10¯¹¹ × 3 × / 0.01²
F = 6.003×10¯¹⁰ / 1×10¯⁴
F = 6.003×10¯⁶ N
Thus the gravitational attraction is 6.003×10¯⁶ N
Answer:
Explanation:
When 238U which is radioactive turns into 206Pb , it becomes stable and no further disintegration is done . Hence in the initial period ratio of 238U undecayed and 206Pb formed will be very high because no of atoms of 238U in the beginning will be very high. Gradually number of 238U undecayed will go down and number of 206Pb formed will go up . In this way the ratio of 238U and 206Pb in the mixture will gradually reduce to be equal to one or even less than one .
In the given option we shall calculate their raio
1 ) ratio of 238U and 206Pb = 5
2 ) ratio of 238U and 206Pb = 4
3 )ratio of 238U and 206Pb = 1
4 ) ratio of 238U and 206Pb = 20
5 )ratio of 238U and 206Pb = 3
lowest ratio is 1 , hence this sample will be oldest.
Ranking from youngest to oldest
4 , 1 , 2 , 5 , 3 .
It's 100% false, it wastes a ton (sorry for the bad pun!) of gas.
