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Explain, with reference to the Schwarzschild radius, why the sun isn’t a black hole.

The Schwarzschild radius of the sun can be calculated using Rs= (2GM)/c 2 . Substitute in the mass of the sun (M=2 10 30 ), the speed of light (c=3 10 8 ), and the universal gravitational constant (G=6.674 1...
LB
Answered by Libbie B. • Physics tutor
5963 Views

Explain how the resistance of a filament lamp changes as the potential difference across it increase

As the potential difference across the filament lamp increases the current across the lamp also increases due to Ohm's law.The increase in current flow also causes the lamp to heat up which causes the resist...
FB
Answered by Fraser B. • Physics tutor
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What are Newton's 3 laws of motion?

Newtons first law states that is an object is moving it will continue to do so in a constant direction and uniform velocity unless acted upon by an external force.Newtons second law states that the change in...
MZ
Answered by Martynas Z. • Physics tutor
3498 Views

How are radioactive isotopes used in medical practices? Explain the different factors involved.

Radioactive isotopes are useful as they can be detected. Detecting these waves can help us find problems within the body and come up with prognoses. An example of this is PET scans. These use substances that...
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Answered by Iffshah I. • Physics tutor
2445 Views

How would our Sun's luminosity change if we increased its temperature 3 times?

The luminosity of our Sun could be derived by the Stefan-Boltzmann, otherwise known as Luminosity law. It says the total energy produced by a unit surface per unit time area (power per unit area) is: (power ...
DG
Answered by Denislav G. • Physics tutor
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