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ValentinkaMS [17]
3 years ago
10

The half-life of iodine-131 is 8 days. Chan Hee examines two samples of iodine-131. Sample 1: 10 g Sample 2: 20 g What can Chan

Hee expect to observe about the samples after 16 days?
a. The mass of iodine-131 in sample 1 will be 7.5 g and in sample 2 will be 16 g.
b. Three-fourths of each sample will have undergone radioactive decay.
c. Ten grams of each sample will have undergone radioactive decay.
d. One-half of each sample will still be iodine-131.
Physics
1 answer:
Illusion [34]3 years ago
4 0
Chan Hee can expect to observe about the samples after 16 days is that three-fourths of each sample will have undergone radioactive decay. The best answer is letter B.
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An ideal Diesel cycle has a compression ratio of 18 and a cutoff ratio of 1.5. Determine the (1) maximum air temperature and (2)
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Answer:

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(2) The rate of heat addition is 215.5 kW

Explanation:

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Therefore,

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(2)

\frac{v_4}{v_3} =\frac{v_4}{v_2} \times \frac{v_2}{v_3}  = \frac{v_1}{v_2} \times \frac{v_2}{v_3} = 18 \times \frac{1}{1.5} = 12

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Heat rejected per kilogram is given by the following relation;

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The efficiency is given by the following relation;

\eta = 1-\frac{\beta ^{k}-1}{\left (\beta -1  \right )r_{v}^{k-1}}

Where:

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Plugging in the values, we get;

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Heat supplied = \frac{150}{0.5191}  = 288.978 \ hp

Therefore, heat supplied = 215491.064 W

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The rate of heat addition = 215.5 kW.

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