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3 years ago

15

Which of the following statements about matter is true? Mass and matter are always the same. Matter is made up of atoms and has

mass. Mass can decrease while matter increases. Matter does not exist in the biosphere.

1 answer:

Zepler [3.9K]3 years ago

7 0

The correct answer is Matter is made up of atoms and has mass.

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A guitar string of length L = 0.79 m is oriented along the x-direction and under a tension of T = 74 N. The string is made of st

Orlov [11]

Answer:

74 N

Explanation:

T = Tension in the string = 74 N

$\rho$ = Density of the steel = 7800 kg/m³

A = Area = $\pi r^2$

r = Radius = $8.5\times 10^{-4}\ m$

Linear density is given by

$\mu=\rho A\\\Rightarrow \mu=7800\times \pi (8.5\times 10^{-4})^2\\\Rightarrow \mu=0.0177\ kg/m$

The linear density is 0.0177 kg/m

Velocity is given by

$v=\sqrt{\dfrac{T}{\mu}}\\\Rightarrow v=\sqrt{\dfrac{74}{0.0177}}\\\Rightarrow v=64.65903\ m/s$

The velocity of the wave on the guitar string is 64.65903 m/s

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3 years ago

____ is a chemical messenger released by virus infected cells

MaRussiya [10]

Answer:

Cytokines is the answer

Explanation:

it is another word for the chemical messanger

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3 years ago

A student is given a sample of matter and asked to determine whether it is an element.

Pepsi [2]

I think the correct answer is C

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What is the current produced by the solar cells of a pocket calculator through which 4.00 C of charge passes in 4.00 hr? Give yo

AfilCa [17]

The average current passing through a device is given by:

I = Q/Δt

I is the average current

Q is the amount of charge that has passed through the device

Δt is the amount of elapsed time

Given values:

Q = 4.00C

Δt = 4.00hr = 14400s

Plug in the values and solve for I:

I = 4.00/14400

I = 0.000277777778A

I = 0.278mA

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3 years ago

How much sweat (in ml ) would you have to evaporate per hour to remove the same amount of heat a 150 w light bulb produces in an

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3 years ago