Answer:
A simple arrangement by means of which e.m.f,s. are compared is known as?
(a)Voltmeter
(b)Potentiometer
(c)Ammeter
(d)None of the above
Explanation:
Electromagnetic waves can travel through a vacuum. Because they do not give up energy
in traveling, Electromagnetic waves can cross the great distances that separate stars
and galaxies. Rays from the Sun travel nearly 150 million
kilometers to reach Earth's surface.
Answer:
12 mins
Explanation:
The distance covered is 5 km, divide this by 25 to get the fraction of an hour it takes. Doing this you get .2, times this by 60 min (1 hour) to get how many mins it takes
Since the bridge and all segments of it are static, the sum of the torques acting on any portion of the bridge you choose is zero for any pivot <span>point you may choose. See if you can find a rigid portion of the bridge and a wisely chosen pivot to which you can apply this powerful fact.
</span>Consider the triangular portion shown in bold and let x be the pivot. (This choice eliminates the torques
due to the tensions in the beams that attach at
point x.) Find the torques on this left hand
triangle (which can be considered a solid piece
because of the connections). Remember that
counterclockwise torque is positive. Assume
that the horizontal segment above is being
stretched, so that the force that the tension in
this segment exerts on the bold triangle is
directed to the right.
Express the torque in terms of T, L , and Fp.
Answer in terms of T and L :
Tt = (TL.sqrt 3) / 2
Summation Tx = -LFp - T sqrt[L^2 - (L/2)^2]
The negative value of the tension shows that the segment is actually under a compressible load. <span />
Answer:
The transmitted intensity through all polarizers = 34.73
Explanation:
Given :
Incident intensity = 
Angle between the transmission axis and polarizer optic axis = 18°
According to the malus law, when unpolarized or polarized light passes through polarizing disk, the intensity of the transmitted light is directly proportional to the square of the cosine of angle between the transmission axis and polarizer optic axis.
∴ 
Where
transmitted intensity,
incident intensity,
angle between the transmission axis and polarizer optic axis.
Here, there are four polarizing disks so that.
from first disk,
∴
₁
18°
=
×
= 
Now
₁ behave as an incident light for second polarizer so we only multiply
term
so we write,
∴
₂ =
×

From third polarizer,
∴
₃ =
×

From forth polarizer,
∴
₄ =
×

Therefor, the the transmitted intensity through forth polarizer = 34.73
.