Answer:
A=
Explanation:
We have given power =40 W but only 10% of this power is used so actual power
We know that from Stefan's law where is Boltzmann constant which value is
So
A=
Answer:
Electrostatics is a branch of physics that studies electric charges at rest. Since classical physics, it has been known that some materials, such as amber, attract lightweight particles after rubbing. The Greek word for amber, or electron, was thus the source of the word 'electricity'.
OzsnuhgnowgnwrfoqingoiwrgWWR KEFQF QEFI FBI O8QE VU F8EINFOQIHWJ OU JN K kjbJ IUJ j osd sfljvbwj 9 oirs jf bhfb wjsf jfow vj isfobsfjb io jio ofsjb
Answer:
In order to improve visibility
Explanation:
Infrared telescopes are made using infrared cameras that contain infrared detectors which are solid-state and are maintained at very cold (cryogenic) temperatures
Infrared radiation is absorbed by water vapor which is present in the Earth's atmosphere, leading to the limitation of the use of infra red telescopes at high altitudes such as mountains, high flying planes or satellites
Answer:
Approximately (assuming that the melting point of ice is .)
Explanation:
Convert the unit of mass to kilograms, so as to match the unit of the specific heat capacity of ice and of water.
The energy required comes in three parts:
- Energy required to raise the temperature of that of ice from to (the melting point of ice.)
- Energy required to turn of ice into water while temperature stayed constant.
- Energy required to raise the temperature of that newly-formed of water from to .
The following equation gives the amount of energy required to raise the temperature of a sample of mass and specific heat capacity by :
,
where
- is the specific heat capacity of the material,
- is the mass of the sample, and
- is the change in the temperature of this sample.
For the first part of energy input, whereas . Calculate the change in the temperature:
.
Calculate the energy required to achieve that temperature change:
.
Similarly, for the third part of energy input, whereas . Calculate the change in the temperature:
.
Calculate the energy required to achieve that temperature change:
.
The second part of energy input requires a different equation. The energy required to melt a sample of mass and latent heat of fusion is:
.
Apply this equation to find the size of the second part of energy input:
.
Find the sum of these three parts of energy:
.