Answer:1.27
Explanation:
Given
incident angle
refracted angle
Suppose is the refractive index of material then using Snell's law we can write
where =refractive index of air
Answer:
Explanation:
The sensor contains an LDR which has a resistance of 10kohlms in daylight and 100kohlms in the dark.
If the resistor in the circuit is 1 megaohlm, the total resistance in daylight and darkness will be 1.01 megaohms and 1.1 megaohlms.
The percentage difference = (1.1-1.01)/1.1*100% = 8.18%
If the resistor in the circuit is 25 kohlm, the total resistance in daylight and darkness will be 35 kohms and 125 kohlms.
The percentage difference = (125-35)/125*100% = 72%
With the input p.d to the sensing circuit fixed at 12 v, the sensing current will change according to the total resistance. A 72% difference is much more detectable. So the 25 kohm resistor is the better choice.
Answer:
(a)
(b)
(c)
Explanation:
First change the units of the velocity, using these equivalents and
The angular acceleration the time rate of change of the angular speed according to:
Where is the original velocity, in the case the velocity before starting the deceleration, and is the final velocity, equal to zero because it has stopped.
b) To find the distance traveled in radians use the formula:
To change this result to inches, solve the angular displacement for the distance traveled ( is the radius).
c) The displacement is the difference between the original position and the final. But in every complete rotation of the rim, the point returns to its original position. so is needed to know how many rotations did the point in the 890.16 rad of distant traveled:
The real difference is in the 0.6667 (or 2/3) of the rotation. To find the distance between these positions imagine a triangle formed with the center of the blade (point C), the initial position (point A) and the final position (point B). The angle is between the two sides known. Using the theorem of the cosine we can find the missing side of the the triangle(which is also the net displacement):
Answer:
The temperature would fall.
Explanation:
The question can be solved by using first law of thermodynamics.
The law states:
The change in internal energy of the system is equal to the heat energy supplied to the system minus the workdone by the system.
ΔU = Q - W
where ΔU is change in internal energy of the system
Q is energy given to the system
W is workdone by the system
Because the charges are repelling each other it means they will move away from each other and their repulsive forces will do positive workdone (workdone is defined as distance moved in the direction of the force applied). Therefore W > 0.
There is no energy supplied to the system so Q = 0.
Using the relation ΔU = Q - W we can see that if Q = 0 and W > 0 then ΔU < 0. Hence internal energy of the system falls so the temperature falls.