There is a missing part in the question. Found the complete text on internet:
"<span>What is the largest size vehicle (kg) it can lift if the diameter of the output line is 28.0 cm? "
Solution
The diameter of the piston is 28.0 cm, this means its radius is 14.0 cm (half the diameter), so the area of the piston is
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The maximum pressure of the lift is
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Therefore the maximum force the piston can lift is
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And the size (the mass) of the vehicle is
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When light ray pass from air into water, its speed and wavelength change only the frequency of the light doesn't change.
Light travels slower in a medium of higher refractive index. It bends because of this change in speed. The wavelength of light also changes in order to maintain the constant frequency.
Wave is a disturbance or energy that propagate through medium from one point to other point
So basically it is a flowing energy that flows into the medium and hence medium particles start oscillating about their mean position to and fro.
This motion of medium particles or this to and fro motion is about their mean position and this will always be cyclic or periodic motion
This means the disturbance or energy continuously flow through the medium such that it will change the position of medium particle and this will be cyclic in order
For an example

so here above equation of wave is a travelling wave in which displacement of medium particle from its mean position is given by "y"
Now we can see that this disturbance depends upon the sine function and it will repeat its same position after every 2 pi time interval as it is cyclic function for this value
Due to this phenomenon of repeatation of its same position we can say that it is disturbance of wave is cyclic.
Answer:
The answer is B.
Explanation:
Given that the <em>current </em>(Ampere) in a series circuit is same so we can ignore it. We can assume that the total voltage is 60V and all the 3 resistance are different, 20Ω, 40Ω and 60Ω. So first, we have to find the total resistance by adding :
Total resistance = 20Ω + 40Ω + 60Ω
= 120Ω
Next, we have to find out that 1Ω is equal to how many voltage by dividing :
120Ω = 60V
1Ω = 60V ÷ 120
1Ω = 0.5V
Lastly, we have to calculate the voltage at R1 so we have to multiply by 20 (R1) :
1Ω = 0.5V
20Ω = 0.5V × 20
20Ω = 10V