When a star uses up all of it's energy and begins to die, it swells up to become a red giant star. This causes its surface gravity to decrease, thereby allowing some of its mass to escape into space.
A binary star is a pair of stars that orbit each other because of their gravitational attraction to each other. When one member of the binary pair uses up all of its energy and begins to die, it loses mass due to the reduction in surface gravity. But instead of escaping into space, this mass is attracted to the companion star because of its gravitational pull. That increases the mass of the companion star. In a process that takes thousands of years, enough matter is transfered that causes the temperature and pressure to increase sufficiently to result in nuclear fusion reactions on the companion star. When these nuclear reactions become extremely violent, the released nuclear energy increases the brightness of this companion star dramatically, thereby creating a nova.
Therefore, it is the dying of one of the stars in a binary system along with a sufficient transfer of star mass to sustain nuclear reactions that results in a nova.
Answer:
acceleration = 0.022 m/s^2
distance = 8.3 x 10^7 m
speed = 1.9 x 10 ^3 m/s
Explanation:
the parameters given are:
mass = 900kg
force = 20N
- from the formula force = mass x acceleration
acceleration = force / mass
acceleration = 20 / 900
acceleration = 0.022 m/s^2
- distance travelled in 1 day (86,400 seconds) = (1/2) x a x t^2
(1/2) x 0.022 x (86,400^2) = 8.3 x 10^7 m
- speed of the sun yatch (v) = a x t
0.22 x 86400 = 1.9 x 10 ^3 m/s
Answer:

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♨ Question :
- A car starts from rest and is moving at 60.0 m/s after 7.50 s. What is the car's average acceleration ?
♨ 
☄ Given :
- Initial velocity ( u ) = 0
- Final velocity ( v ) = 60.0 m/s
- Time ( t ) = 7.50 s
☄ To find :
✒ We know ,

Substitute the values and solve for a.
➛ 
➛ 
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✑ Additional Info :
- When a certain object comes in motion from rest , in the case , initial velocity ( u ) = 0
- When a moving object comes in rest , in the case , final velocity ( v ) = 0
- If the object is moving with uniform velocity , in the case , u = v.
- If any object is thrown vertically upwards in the case , a = -g
- When an object is falling from certain height , in the case , final velocity at maximum height ( v ) = 0.
Hope I helped!
Have a wonderful time ツ
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<u>Answer:</u>
A perfect example of wave reflection is an <u>echo</u>.
<u>Explanation:</u>
A wave reflection takes place when waves cannot pass through a surface and in turn they bounce back. It is not necessary that wave reflections can only happen with sound waves, they can also take place in light waves. Also, the waves which are reflected have the same frequency as the original wave, but their direction is different. When a wave strikes an object in the same angle, they bounce back straight but when they hit an object with different angle, their direction changes.
<span>The heliocentric model of the
universe was proposed by Nicolaus Copernicus. There are numerous scientist in
ancient times who try to explain what happens in the universe. He may not be
the first one who proposed that what astronomical body is the center of the
universe. However, he stated that the center of the universe was the sun, not
the earth. And the earth revolves around it. It is in his book on the
Revolutions of the Heavenly Bodies. It was only published as he lay in his
deathbed. </span>