A uniform metal wire of length $$l$$ has $$10 \Omega$$ resistance. Now this wire is stretched to a length $$2l$$ and then bent to form a perfect circle. The equivalent resistance across any arbitrary diameter of that circle is
The spectral series which corresponds to the electronic transition from the levels $$n_2=5,6, \ldots$$ to the level $$n_1=4$$ is
Given below are two statements: One is labelled as Assertion $$\mathbf{A}$$ and the other is labelled as Reason $$\mathbf{R}$$.
Assertion A: Houses made of concrete roofs overlaid with foam keep the room hotter during summer.
Reason R: The layer of foam insulation prohibits heat transfer, as it contains air pockets.
In the light of the above statements, choose the correct answer from the options given below.
A particle executing simple harmonic motion with amplitude A has the same potential and kinetic energies at the displacement