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3 years ago

14

You want to create a device to warm food that is safe. Which type of electromagnetic wave would be most useful to investigate? A

) X–rays. B) infrared waves. C) gamma rays. D) ultraviolet waves

2 answers:

Liono4ka [1.6K]3 years ago

8 0

The best type of electromagnetic wave to use to warm food that is safe would be the infrared wave. The correct answer is B.

balandron [24]3 years ago

3 0

I think it is infrared because it is closer to microwave which is used to warm food

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A converging lens of focal length 20 cm is placed in contact with, and to the left of, a diverging lens of focal length 30 cm. I

scZoUnD [109]

Answer:

Magnification will be equal to 3

Explanation:

We have given focal length of the converging lens $F_1=20cm$

Focal length of the diverging lens $F_2=30cm$

Object is placed 40 cm to the length of the converging lens d = 40 cm

Combination of the focal length will be equal to

$\frac{1}{F}=\frac{1}{F_1}+\frac{1}{F_2}$

$\frac{1}{F}=\frac{1}{20}+\frac{1}{-30}=\frac{1}{20}-\frac{1}{30}=\frac{1}{60}$

F = 60 cm

So combination of the focal length will be 60 cm

Magnification is given by

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Trucks can be run on energy stored in a rotating flywheel, with an electric motor getting the flywheel up to its top speed of 20

Genrish500 [490]

Answer:

The time it can operate between chargins in minutes is

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Explanation:

Given: $m=500kg$ , $r=1.0m$ , $w=200\pi rad/s$

a). The rotational kinetic energy

$K_R=\frac{1}{2}*I*w^2$

$I=\frac{1}{2}*m*r^2$

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$K_R=49.348x10^6J$

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Snezhnost [94]

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