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2 years ago

At what angle should the axes of two Polaroids be placed so as to reduce the intensity of the incident unpolarized light to

Physics

1 answer:

mote1985 [20]2 years ago

6 0

Answer:

Ok, the question is incomplete buy ill try to answer this in a general way.

Suppose that you have no-polarized light.

When that light hits one polaroid, the light becomes polarized along some line, and has an intensity I0.

Now, when polarized light hits a polaroid which axis is at an angle θ with respect to the polarization of the light, the intensity of the resulting beam is given by the Malus's law:

I(θ) = I0*cos^2(θ)

For example, if the axis of the polaroid is exactly the same as the one of the polarized light, then we have θ = 0°

and:

I(0°) = I0*cos^2(0°) = I0

So the intensity does not change.

Now, knowing the initial intensity, you can find the angle needed to get a given intensity.

For example, if the question was:

"At what angle should the axes of two Polaroids be placed so as to reduce the intensity of the incident unpolarized light to A"

We should solve:

I(θ) = A = I0*cos^2(θ)

(A/i0) = cos^2(θ)

√(A/I0) = cos(θ)

Acos(√(A/I0)) = θ

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Kobotan [32]

Any two-dimensional vector in cartesian (x,y) coordinates can be broken down into individual horizontal and vertical components using trigonometry. If a train goes up a hill with 15 degree incline at a speed of 22 m/s, the horizontal component is 22cos(15)=21.3 m/s and the vertical component is 22sin(15)=5.5 m/s.

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2 years ago

Margy is trying to improve her cardio endurance by performing an exercise in which she alternates walking and running 100.0 m ea

madreJ [45]

In order to answer this exercise you need to use the formulas

S = Vo*t + (1/2)*a*t^2

Vf = Vo + at

The data will be given as

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And now you do the following:

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and

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2 years ago

Read 2 more answers

The capacitors in each circuit are fully charged before the switch is closed. Rank, from longest to shortest, the length of time

8_murik_8 [283]

The concept used in this is circuit analysis using the simplification of resistors and capacitors.

Explanation:

The time constant for each of the circuits in figure A, B, C, D and E. Therefore, rank the length of time the bulbs stay lit from longest to shortest by using the value of time constant for each circuit. The rank of the time constant of the circuit is C > A = E > B > DC > A = E > B > D.

Capacitance is the central concept in electrostatics and constructed devices called capacitors are essential elements of electronic circuits.

If more charge is placed on the conductor the voltage increases proportionately. The ratio of the charge to the voltage is called the capacitance C of the conductor C= q/v.

The resistance increases if you add resistors in series and decreases if you add them in parallel. on the other hand the capacitors increases if it is added parallel and decreases if added in series. hence the circuit longest time constant takes longest time to discharge.

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2 years ago

A gymnast's backflip is considered more difficult to do in the layout (straight body) position than in the tucked position. Why?

spin [16.1K]

Answer:

The body's rotational inertia is greater in layout position than in tucked position. Because the body remains airborne for roughly the same time interval in either position, the gymnast must have much greater kinetic energy in layout position to complete the backflip.

Explanation:

A gymnast's backflip is considered more difficult to do in the layout (straight body) position than in the tucked position.

When the body is straight , its moment of rotational inertia is more than the case when he folds his body round. Hence rotational inertia ( moment of inertia x angular velocity ) is also greater. To achieve that inertia , there is need of greater imput of energy in the form of kinetic energy which requires greater effort.

So a gymnast's backflip is considered more difficult to do in the layout (straight body) position than in the tucked position.

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2 years ago

Two identical grasshoppers jump into the air with the same initial speed and experience no air resistance. Grasshopper A goes st

avanturin [10]

Answer:

a.) At their highest point, both of them have the same amount of mechanical energy.

Explanation:

Grasshopper A jumps upwards with speed v while grasshopper B jumps at an angle of 66 degree with horizontal at same speed

so vertical speed of B is given

$v_y = v sin66 = 0.91v$

$v_x = v cos66 = 0.41v$

So when both the grasshopper will jump upwards they both will attain different maximum heights

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So mechanical energy of grasshopper A is given as

$U = \frac{1}{2}mv^2$

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$U = \frac{1}{2}m(vcos^2\theta) + \frac{1}{2}m(vsin\theta)^2$

$U = \frac{1}{2}mv^2$

So we have

a.) At their highest point, both of them have the same amount of mechanical energy.

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1 year ago