Answer:
B) 2
Explanation:
Significant figures : The figures in a number which express the value -the magnitude of a quantity to a specific degree of accuracy is known as significant digits.
The rule apply for the multiplication and division is :
The least number of significant figures in any number of the problem determines the number of significant figures in the answer.
The rule apply for the addition and subtraction is :
The least precise number present after the decimal point determines the number of significant figures in the answer.
(3.478-2.31) = 1.168 ≅ 1.17 (Rounded to least decimal digit)
(4.428-3.56) = 0.868 ≅ 0.87 (Rounded to least decimal digit)
So,
1.17 * 0.87 = 1.0 (Rounded to least significant)
Answer - two significant digits
Answer:
Explanation:
A solar collector is a device that absords Sun's heat energy to heat air or water. It is majorly used for heating purpose, and do not generate electricity directly.
The flow tubes and collector plate are black in color so as to increase the intensity of heat generated by the collector. A black body is a good absorber of heat, it absorbs most heat directed to the collector. Also, a black body is a good radiator of heat, the heat absorbed is rediated to the appropriate channels for the heating of water or air molecules. The black color increases the efficeincy and percentage of solar energy absorbed by the collector.
If a reflective color is used (e.g white), major percentage of the incident heat would be reflected. This would decrease the efficiency of the solar collector.
Answer:
0.00757 grams
Explanation:
Find the molar mass of the compound: which is 60.05.
The molar mass is basically just the sum of all the atomic masses of each of the elements.
Then multiply the molar mass by the number of moles in the compound, which is 1.26 x 10^-4 moles.
Your answer should be 0.00757 grams.
