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Kamila [148]
2 years ago
14

Help please!

Physics
1 answer:
weeeeeb [17]2 years ago
5 0

Answer:

m=1000kg

v=72km/h=20m/s

Work = different of kinetic energy

W= ½ mv ²

W= ½ ×1000×20×20= 400000J

also written as 4×10^5 J

thank you

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Consider a double-slit with a distance between the slits of 0.04 mm and slit width of 0.01 mm. Suppose the screen is a distance
scZoUnD [109]

Answer:

The distance between the places where the intensity is zero due to the double slit effect is 15 mm.

Explanation:

Given that,

Distance between the slits = 0.04 mm

Width = 0.01 mm

Distance between the slits and screen = 1 m

Wavelength = 600 nm

We need to calculate the distance between the places where the intensity is zero due to the double slit effect

For constructive fringe

First minima from center

x_{1}=\dfrac{\lambda D}{2d}

Second minima from center

x_{2}=\dfrac{3\lambda D}{2d}

The distance between the places where the intensity is zero due to the double slit effect

\Delta x_{d}=x_{2}-x_{1}

\Delta x_{d}=\dfrac{3\lambda D}{2d}-\dfrac{\lambda D}{2d}

\Delta x_{d}=\dfrac{\lambda D}{d}

Put the value into the formula

\Delta x_{d}=\dfrac{600\times10^{-9}\times1}{0.04\times10^{-3}}

\Delta x_{d}=0.015 =15\times10^{-3}\ m

\Delta x_{d}=15\ mm

Hence, The distance between the places where the intensity is zero due to the double slit effect is 15 mm.

8 0
3 years ago
Coming to the bottom of a mountain, a skier moving with speed v collides with a barrier and is brought to a stop in an amount of
IRISSAK [1]

Answer:

Explanation:

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The given case is as follows

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in the second case

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option a) is correct .

iii )

In the last case

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Liters

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3 years ago
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Calculate the acceleration of an airplane that starts at rest and reaches a speed 45m/s in 9 seconds
sasho [114]

I believe the acceleration would be 5m/s

All you would need to do is divide the final speed by the time it took to get there. I am only about 80 sure this answer is correct, so take my advise only if you feel comfortable.

3 0
3 years ago
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Suppose a certain car supplies a constant deceleration of A meter per second per second. If it is traveling at 90km/hr. When. th
aksik [14]

Answer:

i)-6.25m/s

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then apply the same formula as that in (i)

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