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3 years ago

Explain in detail molecular behavior from a hot brick to a cold brick

Physics

1 answer:

slava [35]3 years ago

3 0

Answer:

by conduction, or the transfer of energy from matter to adjacent matter by direct contact, without intermixing or flow of any material. by convection, or the transfer of energy by the bulk mixing of clumps of material. In natural convection it is the difference in density of hot and cold fluid which causes the mixing.

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As the result of a thermal inversion the prevailing air temperature profile increases 1°C/100m above the ground level. To what m

astra-53 [7]

Answer:

909.1 m

Explanation:

Rate of temperature increase with 100 m elevation = 1°C

h = Maximum Height

Adiabatic lapse rate = -0.65°C/100 m

We have the relation

$\dfrac{1^{\circ}C}{100}=\dfrac{15^{\circ}C}{h}+\left(-\frac{0.65}{100}\right)\\\Rightarrow \dfrac{1^{\circ}C}{100}+\left(-\frac{0.65}{100}\right)=\dfrac{15^{\circ}C}{h}\\\Rightarrow h=\dfrac{15^{\circ}C}{1.65^{\circ}C}\times 100\\\Rightarrow h=909.1\ m$

The maximum height is 909.1 m

5 0

3 years ago

A man takes 20 seconds to climb 5m up a ladder. He weighs 720N. Calculate the power he must deliver to do this.

Inessa05 [86]

Answer:

180 W

Explanation:

The work done by the man against gravity is equal to its gain in gravitational potential energy:

$W=mg\Delta h$

where

(mg) = 720 N is the weight of the man

$\Delta h= 5 m$ is the change in height

Substituting,

$W=(720)(5)=3600 J$

The power he must deliver is given by

$P=\frac{W}{t}$

where

W = 3600 J

t = 20 s is the time taken

Substituting,

$P=\frac{3600}{20}=180 W$

3 0

3 years ago

a car travels at 15 m/s for 10 s. It then speeds up with a constant acceleration of 2.0 m/s? for 15 s. At the end of this time,

Firlakuza [10]

V = u + at where u is initial velocity (15 m/s), a is acceleration (2m/s^2) and t is time (15 seconds)

V = 15 + 2 X 15

V = 45 m/s

6 0

3 years ago

What is the difference between flashing point, boiling point and melting point

sp2606 [1]

<h3><u>Answer and explanation;</u></h3>

<u>Melting point</u> is defined as the temperature at which solid and liquid phases are in equilibrium. It is the temperature at which a solid changes state from solid to liquid at atmospheric pressure.
<u>Boiling poin</u>t is the temperature at which the vapour pressure of a liquid is equal to the external pressure. It is the temperature at which a substance changes from a liquid into a gas.
<u>The flash point </u>of a flammable liquid or volatile liquid is the lowest temperature at which it can form an ignitable mixture in air. At this temperature the vapor may cease to burn when the source of ignition is removed.

8 0

3 years ago

Read 2 more answers

An interstellar space probe is launched from Earth. After a brief period of acceleration it moves with a constant velocity, 70.0

sleet_krkn [62]

Answer:

22.26 years

, 15.585 light years , 11.13 light years

Explanation:

$t' = t/(\sqrt{1-(v/(c*v)/c)}$