A conducting circular loop is placed in a uniform magnetic field $$\mathrm{B}=0.125 \mathrm{~T}$$ with its plane perpendicular to the loop. If the radius of the loop is made to shrink at a constant rate of $$2 \mathrm{~mm} \mathrm{~s}^{-1}$$, then the induced emf when the radius is $$4 \mathrm{~cm}$$ is
Figure below shows a lens of refractive index, $$\mu=1.4$$. $$C_1$$ and $$C_2$$ are the centres of curvature of the two faces of the lens of radii of curvature $$4 \mathrm{~cm}$$ and $$8 \mathrm{~cm}$$ respectively.
The lens behaves as a
The temperature of a wire is doubled. The Young's modulus of elasticity
A wire of length $$2 \mathrm{~m}$$ carries a current of $$1 \mathrm{~A}$$ along the $$\mathrm{x}$$ axis. A magnetic field $$B=B_0(i+j+k)$$ tesla exists in space. The magnitude of magnetic force on the wire is