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=
An atom is defined as having the same number of electrons (negative charge), protons (positive charge) and neutrons (no charge). This means that it will have the same amount of negative and positive charge, giving it a net zero charge. On the other hand, an ion has different amount of electrons and protons.
the Doppler effect. (I don't know how to explain it lol)
Answer:
The Eurasian Plate
Explanation:
The Eurasian plate is one of the most extended on Earth, crossing all of Asia and Europe. The Eurasian plate is between the North American and the African Plates on the north and west sides. The Eurasian plate crushed up above the Indian plate. The Tibetan plateau and the Himalayan mountain range formed due to the crush between the Eurasian Plate and Indian Plate, which started 50 million years ago.
The part that causes the disc caliper piston to retract when the brakes are released is the square-cut O-ring.
The square cut seal is the most important part of a disc brake caliper, for keeping the brake behind the piston so that when you step on the brake pedal, it releases a pressure that applied to the piston which in return applies the pad to the rotor.