<h3><u>Answer</u>;</h3>
= 22°
<h3><u>Explanation</u>;</h3>
- According to Snell's law, the ratio of the sine of the angle of incidence to the sine of the angle of refraction is a constant. The constant value is called the refractive index of the second medium with respect to the first.
- Therefore; Sin i/Sin r = η
In this case; Angle of incidence = 90° -60° =30°, angle of refraction =? and η = 1.33
Thus;
Sin 30 / Sin r = 1.33
Sin r = Sin 30°/1.33
= 0.3759
r = Sin^-1 0.3759
= 22.08
<u>≈ 22°</u>
<span>In order to calculate an average, we should sum all numbers and divide them by quantity.
Let’s work with qualifications first. Let’s say you got a 10 in 1 exam, then an 8 in 2 exams and a 4 in 2 exams. Your average will be:
= (10*1+8*2+4*2) / 5 = 6.8
If 6 is the minimum, you will pass.
There is another way to calculate this average: applying distributive property.
= 10*1/5+8*2/5+4*2/5 = 6.8
Remember you can convert the fractions into equivalent fractions: 1/5 = 20/100; 2/5 = 40/100
= 10*20/100+8*20/100+4*20/100 = 6.8
We actually don’t have the number of atoms of each mass… we have the percentage instead! So we need to learn this last method for atoms.
Let’s go back to our atoms problem:
73.71 % of atoms have a mass of 27.98 u
14.93 % of atoms have a mass of 28.98 u
11.36 % of atoms have a mass of 29.97 u
So let’s put that in the formula:
Average mass = 27.98 u*73.71 /100 + 28.98 u*14.93 /100 + 29.97u*11.36 /100
So what you have to know is that a percentage can be converted into a fraction, and you should work that fraction in order to find the average. We can make the calculus shorter putting 100 as the common denominator:
Average mass = (27.98 u*73.71 + 28.98 u*14.93 + 29.97u*11.36)/100
So actually we are taking the percentage as if it was the quantity, and 100 as if it was the total (the total of all percentages is always 100). Maybe we don’t have 100 atoms, but it will be the same proportion anyway, whatever number we have! And here it is the result:
Average mass = 28,36u
</span>
Answer:
874.2 KJ
Explanation:
Ethyl alcohol boiling point = 78oC, freezing point = -114oC heat of vaporization = 879 kJ/kg heat of fusion = 109kJ/Kg specific heat capacity (c) of ethyl alcohol = 2,43KJ/Kg.k
calculating each heat drawn singly
Quantity loss due vaporization = m × Lv where m is mass in kg and Lv is the heat of vaporization
Quantity of heat loss due to fusion = m × Lf ( heat of fusion)
Quantity of heat loss due to cooling from 78oc to -114 = m × c × ΔT 9 (change in Temperature)
Quantity of heat removed due to vaporization = 0.601 ×879 = 528.279 KJ
Quantity of heat lost due to cooling from 78oc to -114oc = mcΔT= 0.601 × 2.43 × ( 78 - (-114)) = 0.601 ×2.43 × 192 = 280.4 kJ
Quantity of heat lost due to fusion during freezing = 0.601 × 109 = 65.509 KJ
Total heat removed = sum of the each quantity of heat removed from the gaseous ethyl alcohol = 528.279 + 280.4 + 65.509 = 874.2 KJ
At the highest point of the trajectory the vertical component will have its zero velocity, and the descent caused by the force of gravity will begin.
Since the ball is thrown with a certain speed, the vertical component reaches its highest point (upwards), until returning to the receiver who will receive the ball with the same vertical component but in the opposite direction (downwards).
Therefore the vertical component will have its highest value at launch.
Answer:
B, he will fly off the other end
Explanation:
there is too much potential energy that transforms into kinetic energy for him to stay on the track.
