Which statement best describes why a machine is useful? A machine does a greater amount of work than the amount of work that is
2 answers:
You might be interested in
Answer: (E) 300 bq
Explanation:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.
Radioactive decay process is a type of process in which a less stable nuclei decomposes to a stable nuclei by releasing some radiations or particles like alpha, beta particles or gamma-radiations. The radioactive decay follows first order kinetics.
Half life is represented by
Half life of Thallium-208 = 3.053 min
Thus after 9 minutes , three half lives will be passed, after ist half life, the activity would be reduced to half of original i.e. , after second half life, the activity would be reduced to half of 1200 i.e.
, and after third half life, the activity would be reduced to half of 600 i.e.
,
Thus the activity 9 minutes later is 300 bq.
Answer:
The new temperature of the nitrogen gas is 516.8 K or 243.8 C.
Explanation:
Gay-Lussac's law indicates that, as long as the volume of the container containing the gas is constant, as the temperature increases, the gas molecules move faster. Then the number of collisions with the walls increases, that is, the pressure increases. That is, the pressure of the gas is directly proportional to its temperature.
Gay-Lussac's law can be expressed mathematically as follows:
Where P = pressure, T = temperature, K = Constant
You want to study two different states, an initial state and a final state. You have a gas that is at a pressure P1 and at a temperature T1 at the beginning of the experiment. By varying the temperature to a new value T2, then the pressure will change to P2, and the following will be fulfilled:
In this case:
- P1= 2 atm
- T1= 50 C= 323 K (being 0 C= 273 K)
- P2= 3.2 atm
- T2= ?
Replacing:
Solving:
T2= 516.8 K= 243.8 C
<u><em>The new temperature of the nitrogen gas is 516.8 K or 243.8 C.</em></u>