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3 years ago

A substance freezes at -58c therefore substance melts at ?

1 answer:

3 0

The freezing point is the same as the melting point.

If it freezes at -58°C, hence the melting point is also <span>-58°C.</span>

You might be interested in

calculate the diameter of a silver wire of length 75cm , which is extended by 1.85mm when a 10kg mass is suspended from it's end

sdas [7]

Answer: $0.8\ mm$

Explanation:

Given

length of wire $l=75\ cm$

change in length $\Delta l=1.85\ mm$

mass of wire $m=10\ kg$

Young's modulus for silver $E=7.9\times 10^{10}\ N/m^2$

load on wire $F=mg$

$F=10\times 9.8=98\ kg$

change in length is given by

$\Delta l=\dfrac{Pl}{AE}$

Where A=area of cross-section

$A=\dfrac{Pl}{\Delta lE}$

$A=\dfrac{98\times 0.75}{1.85\times 10^{-3}\times 7.9\times 10^{10}}$

$A=\dfrac{73.5}{14.615\times 10^{7}}$

$A=5.029\times 10^{-7}\ m^2$

also wire is the shape of cylinder so cross-section is given by

$A=\dfrac{\pi d^2}{4}=5.029\times 10^{-7}\ m^2$

$\Rightarrow d^2=\dfrac{5.029\times 10^{-7}\times 4}{\pi }$

$\Rightarrow d^2=64.02\times 10^{-8}$

$\Rightarrow d=8\times 10^{-4}\ m$

$\Rightarrow d=0.8\ mm$

4 0

3 years ago

An electric iron is connected to the mains power supply of 220 V. When the electric iron is

Ilya [14]

Answer:

Given: V = 220V, Pmin = 360W, Pmax = 840W

For minimum heating case:

We know that

Pmin = VI

360 = 220 X I

I = 1.63 amp

R = V/I

R = 220/1.63

R = 134.96ohms

For maximum heating case:

We know that

Pmax = VI

840 = 220 X I

I = 3.81 amp

R = V/I

R = 220/3.81

R = 57.74 ohms

7 0

2 years ago

Explain how you think humans have disrupted the nitrogen cycle HELP QUICK DUE APRIL 15TH ANYBODY

mina [271]

Answer:

Scientists have determined that humans are disrupting the nitrogen cycle by altering the amount of nitrogen that is stored in the biosphere. The chief culprit is fossil fuel combustion, which releases nitric oxides into the air that combine with other elements to form smog and acid rain.

5 0

2 years ago

Your father bought you a pair of shoes. When you wore the shoes you realized there was a problem. The shoes were too long. Why m

Elenna [48]

Answer: This problem may arise when your father never bought a shoe before. A male is bad at buying accesories and guessing the size, so the mother should have bought a pair of shoes. Or it can also be that your father has a short term memory or that he never knew the size of your feets. The feet might also have irregular growth for which it grows more than the normal size but such cases are rare to be seen.

You can prevent this by going with your father and selecting the shoe of your size. Or you can simply send your mother to buy it for you instead. Or another perfect choice could be is that you just dont ever send your father to buy anything for you or just never buy a pair of shoes. Wear the shoes that you always did or buy it yourself since your the one who is supposed to know the size of your feets. Another possible solution could be that you can make use of the money by gifitng them to someone close to you.

5 0

2 years ago

what will happen to the pressure in a gas if you compressed it into a volume that was one third the size? why?

Annette [7]

Answer:

Pressure will triple (Boyle's Law)

Explanation:

Assuming a constant temperature: (compressing gases usually raises the temp significantly):

P1V1 = P2V2

P1V1 / V2 = P2

Now change V2 to 1/3 V2:

P1V1 / (1/3 V2 ) = P2 / (1/3 )

P1V1/ (1/3 v2 ) = 3 P2 <======= THE PRESSURE WILL TRIPLE

This is Boyle's Law

5 0

2 years ago