centre of square disrance to each corner found by Pythagoras' theorem.
coulombs law used to clculate field of each charge at centre
fields added vectorially for res
Answer:

Explanation:
At thermal equilibrium we have heat given by aluminium must be equal to the heat absorbed by the water
so we will have


so we will have

so we have

so we have


Answer:
Explanation:

from steam tables , at 250 kPa, and at
T₁ = 80⁰C ⇒ h₁ = 335.02 kJ/kg
T₂ = 20⁰C⇒ h₂ = 83.915 kJ/kg
T₃ = 42⁰C ⇒ h₃ = 175.90 kJ/kg
we know


according to energy balance equation


Light travelling in a vacuum is the fastest thing in the universe. The speed would be 2.99x10^8 m/s. The answer to this question is 'vacuum', where light can travel the fastest. I hope this helps you. You're welcome!