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3 years ago

10

A current of 8.0 A flows through a resistor when a potential difference of 20.0 V is applied to the resistor. What is the resist

ance of the resistor?

1 answer:

marta [7]3 years ago

3 0

I=U/R (current = potential/resistance)
8=20/r
r=20/8
r=2.5

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5. Why does a Ntion try to influence the value of its currency?

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Answer:

If inflation is relatively lower than competitors, then the countries goods will become more attractive and demand will rise. Lower inflation tends to increase the value of the currency in the long term.

Explanation:

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2 years ago

Coherent light of wavelength 525 nm passes through two thin slits that are 4.15Ã—10^(âˆ’2) mm apart and then falls on a screen 7

IRINA_888 [86]

A) 4.7 cm

The formula for the angular spread of the nth-maximum from the central bright fringe for a diffraction from two slits is

$sin \theta=\frac{n \lambda}{d}$

where

n is the order of the maximum

$\lambda$ is the wavelength

$a$ is the distance between the slits

In this problem,

n = 5

$\lambda=525 nm =5.25\cdot 10^{-7} m$

$a=4.15\cdot 10^{-2} mm=4.15\cdot 10^{-5} m$

So we find

$\theta=sin^{-1} (\frac{(5)(5.25\cdot 10^{-7} m)}{4.15\cdot 10^{-5} m})=3.62^{\circ}$

And given the distance of the screen from the slits,

$D=75.0 cm = 0.75 m$

The distance of the 5th bright fringe from the central bright fringe will be given by

$y=D tan \theta = (0.75 m)tan 3.62^{\circ}=0.047 m = 4.7 cm$

B) 8.1 cm

The formula to find the nth-minimum (dark fringe) in a diffraction pattern from double slit is a bit differente from the previous one:

$sin \theta=\frac{(n+\frac{1}{2}) \lambda}{d}$

To find the angle corresponding to the 8th dark fringe, we substitute n=8:

$\theta=sin^{-1} (\frac{(8+\frac{1}{2})(5.25\cdot 10^{-7} m)}{4.15\cdot 10^{-5} m})=6.17^{\circ}$

And the distance of the 8th dark fringe from the central bright fringe will be given by

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3 years ago

In pairs figure-skating competition, a 65-kg man and his 45-kg female partner stand facing each other both at rest on the ice. I

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The final velocity of her partner is approximately -1.04 m/s or 1.04 m/s in the opposite direction to her direction of motion

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The given parameters are;

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The mass of the woman, m₂ = 45 kg

Taking the relative initial velocity of the man and the woman as 0 m/s, we have;

The initial velocity of the man, v₁₁ = 0 m/s

The initial velocity of the man, v₁₂ = 0 m/s

The final velocity of the woman, v₂₂ = 1.5 m/s

The final velocity of the man = v₂₁

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Which gives;

m₁ × v₁₁ + m₂ × v₁₂ = m₁ × v₂₁ + m₂ × v₂₂

Substituting the known values;

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∴ 65 × v₂₁ + 45 × 1.5 = 0

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The final velocity of the man, her partner = v₂₁ ≈ -1.04 m/s.

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3 years ago

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<em>The 6000 lines per cm grating, will produces the greater dispersion .</em>

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The directions of the light beam produced from a diffraction grating depend on the spacing of the grating, and also on the wavelength of the light.

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(a + b) sin ∅n = nλ

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n is the order of principal maxima

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vova2212 [387]

Answer:

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3 years ago

Read 2 more answers