Answer:
43.7 °C
Explanation:
= Coefficient of linear expansion of brass = 
= Coefficient of linear expansion of steel = 
= Initial length of brass = 31 cm
= Initial length of steel = 11 m
= Total change in length = 3 mm
Total change in length would be
The final temperature is 43.7 °C
Answer:
Hydrogen and helium compounds.
Explanation:
We know that the solar System was formed around <u>4.6 billion years ago, </u>due to the gravitational collapse of a giant interstellar molecular cloud.
This cloud is a type of interstellar cloud and its density and size permit the formation of molecules, most commonly molecular hydrogen.
Therefore the principal substances were found before planets began to form are hydrogen and helium compounds, besides Rocks, metals, most of them in gaseous form.
I hope it helps you!
Answer: A hymn which accompanies religious observances and rituals. And others like guitar, violin, flute, harp and the organ
Explanation: Gradually people instructed the natives not only in singing but also in playing various instruments like guitar, violin, flute, harp and later on, the organ.
Answer:
If the line is curved, the slope is changing, which also means the velocity is changing. In a distance-time graph, the gradient of the line is equal to the speed of the object. The more the gradient (and the steeper the line) the faster the object is moving.
Answer:
B) Within an atom, an electron can have only particular energies.
Explanation:
As we know that electrons have energy but apart from electrons we know that protons and neutrons inside the nucleus of atom will also have energy in them.
rest all the statements are true as we have
A) Electrons orbit the nucleus rather like planets orbiting the Sun.
TRUE, because electrons can move in stationary orbit around the nucleus
C) Electrons can jump between energy levels in an atom only if they receive or give up an amount of energy equal to the difference in energy between the energy levels.
Difference amount of energy is lost or absorbed by the electron in form of photons
D) An electron has a negative electrical charge.
Charge of an electron is given as 
E) Electrons have very little mass compared to protons or neutrons
Mass of an electron is given as
mass of proton or neutron
