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A question on Quantum Entanglement

I have read a lot about quantum mechanics but have a query. using an entangled photon for this question. If you can’t measure an entangled photon without affecting it’s entanglement then how do we know it was even entangled to start with and not just always a certain “spin”, either up or down. How can […]

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How to describe momentum physically ?

Kiran asks: “How do you describe momentum physically by not in definitions like product of mass and velocity?” Answer: Momentum is defined as “Mass in Motion” or “The quantity of motion“. Momentum is a measure of the “effect” a moving body can produce. It is a measure of the “effort” required to bring a body to […]

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Physics Homework

What is refractive index?

Refractive index of a substance is a measure of the relative speed of light through that substance. It tells us by what fraction light is slowed down in the medium. Refractive index = speed of light in vacuum /speed of light in the medium Snell’s law…

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Why ordinary ammeter cannot measure AC?

Ac changes its direction frequently and therefore the ordinary ammeter which is just a galvanometer with a shunt, tends to respond to the magnitude and direction of the instantaneous values of current and in effect it will not show any deflection. Ac is measured using hot wire ammeter, which is based on the heating effect […]

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Plus Two Physics

Do You know? You can prevent most of the virus attacks by logging in as a restricted user !

The viruses get more privileges and access to system files when you are logged in as admin user. So, it is a good idea to create a limited user account for your pc and use it to access internet and for other works where admin powers are not required. Login as admin user only when […]