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3 years ago

Which si unit whould be most appropriate for describing the length of a shoe?

Physics

1 answer:

aniked [119]3 years ago

4 0

Answer:

Milimeters

Explanation:

This kind of question must be checked with everyday elements, in this way we will analyze each of the options until we reach the appropriate:

kilograms can not be because this unit serves to measure the mass not the length.

kilometers (km) is a unit of length, but however it does not serve for this measurement since a km is equivalent to 1000 meters, therefore measuring the length of a shoe with a ruler measuring 1000 meters is very impractical.

milliliters is a unit of volume, and can often be found in the measurement of volume content of liquids, for example 700 milliliters of milk or 1000 milliliters of water. Therefore it is impractical to measure a shoe with a unit of volume.

In this way the way to measure a shoe correctly is using a ruler or measuring instrument graduated in millimeters.

You might be interested in

Make the following conversion. 34.9 cL = _____ hL. 0.349 0.0349 0.00349 349,000

AnnyKZ [126]

Hey there!

Here is your answer:

The proper answer to this question is option C "0.00349".

Reason:

1 L = 100 cL. Or 1 cL = 0.01 L

34.9 cL = 34.9 / 100 L = 0.349 L

 1 hL = 100 L. 0.349 L = 0.349 / 100 hL = 0.00349 hL

Therefore the answer is option C!

If you need anymore help feel free to ask me!

Hope this helps!

~Nonportrit

4 0

3 years ago

Lasers are now used in eye surgery. Given the wavelength of a certain laser is 514 nm and the power of the laser is 1.1 W, how m

Leno4ka [110]

Answer: $1.593*10^{17} photons$ released if the laser is used 0.056 s during the surgery

Explanation:

First, you have to calculate the energy of each photon according to Einstein's theoty, given by:

$E =\frac{hc}{\lambda}$

Where $\lambda$ is the wavelength, $h$ is the Planck's constant and $h$ is the speed of light

$h = 6.626*10^{-34} \frac{m^{2} kg }{s}$ -> Planck's constant

$c = 3*10^{8} \frac{m}{s}$ -> Speed of light

So, replacing in the equation:

$E =\frac{ 6.626*10^{-34} \frac{m^{2} kg }{s}*3*10^{8} \frac{m}{s}}{514*10^-9 m}$

Then, the energy of each released photon by the laser is:

$E = 3.867*10^{-19} \frac{J}{photons}$

After, you do the inverse of the energy per phothon and as a result, you will have the number of photons in a Joule of energy:

$\frac{1}{3.867*10^{-19}} = 2.586*10^{18} \frac{photons}{J}$

The power of the laser is 1.1 W, or 1.1 J/s, that means that you can calculate how many photons the laser realease every second:

$2.586*10^{18}\frac{photons}{J} * 1.1 \frac{J}{s} = 2.844*10^{18} \frac{photons}{s}$

And by doing a simple rule of three, if $2.844*10^{18} photons$ are released every second, then in 0.056 s:

$0.056 s*2.844*10^{18} \frac{photons}{s} = 1.593*10^{17} photons$ are released during the surgery

5 0

3 years ago

You are traveling at 100 km/hr to make it to work on time. You have to be to work in .25 hr or you will be late. You have 16 km

alexgriva [62]

Answer: Yes

Explanation:

Velocity $V$ is defined as the distance traveled $d$ in a specific time $t$ :

$V=\frac{d}{t}$

If you are traveling at $V=100 km/h$ a distance $d=16 m$ , then the time it will take you to be at work is:

$t=\frac{d}{V}=\frac{16 km}{100 km/h}$

$t=0.16 h$

This means you will make it on time, because this time is less than 0.25 h.

4 0

3 years ago

Rust forms when what reacts with chemicals in rocks

Sav [38]

Rust forms when oxygenreacts with chemicals in rocks, and that is often the case

6 0

2 years ago

Read 2 more answers

What is one watt ? Write the relation of watt with kilowatt , megawatt , and horsepower .

alina1380 [7]

Answer:

See the explanation below

Explanation:

The watt (the power) is equal to the relationship between the work and the time in which that work is performed.

$P = W/t$

where:

W = work [J] (units of Joules)

t = time [s].

Now 1000 [W] are equal to 1 [kW]

And 1000000 [W] are equal to 1 [MW]

The horsepower is the unit of power in the imperial system of units.

And 745.7 [W] are equal to 1 [Hp]

3 0

2 years ago