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3 years ago

Select the correct answer.

Physics

1 answer:

Sonbull [250]3 years ago

4 0

Answer: 65°

Explanation:

According to Snell's law, which states that ratio of the sine of the angle of refraction and the sine of the angle of incidence is always constant and equivalent to the ratio of phase velocities of the two mediums it is passing through.

nr / ni = sin I/ sin r

r = 38°

I = ?

ni = 1

nr = 1.47

1.47 / 1 = sin i / sin38

Sin I = 1.47sin38

Sin I = 0.9050

I = sin-¹ 0.9050

I = 64.826°

I = 65°

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shtirl [24]

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Explanation:

For a conductive wire moving perpendicular to a magnetic field, the electromotive force (voltage) induced in the wire due to electromagnetic induction is given by

$\epsilon=BvL$

where

B is the strength of the magnetic field

v is the speed of the wire

L is the length of the wire

For the wire in this problem, we have:

$\epsilon=12 V$ (induced emf)

L = 0.20 m (length of the wire)

v = 3.0 m/s (speed)

Solving for B, we find the strength of the magnetic field:

$B=\frac{\epsilon}{vL}=\frac{12}{(0.20)(3.0)}=20 T$

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3 years ago

If a weightlifter lifts a 286 kg mass 0.25 meters above his head, how much PEg does the mass have?

vazorg [7]

Answer:

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Explanation:

Given:

Mass of the object is, $m=286$ kg

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We know that for a mass $m$ raised to a height $h$ , the change in potential energy is given as:

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Now, plug in the given values and solve.

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3 years ago

Read 2 more answers

What is 7.4 in it's simplest form?

Iteru [2.4K]

Assuming that you mean to ask . . . "What is 7.4 as a fraction in simplest form?"

7.4 = 7 and 4/10

4/10 can be reduced to 2/5

7 represents = (7*5)/5 = 35/5

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or
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2 years ago

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Answer:

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Also Q = It........................ Equation 3.

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