Lenz's law is representing which fundamental conservation law?

$A$ physicist works in a laboratory where the magnetic field is $2 \, T$. She wears a necklace enclosing an area of $0.01 \, m^2$ in such a way that the plane of the necklace is normal to the field,and it has a resistance $R = 0.01 \, \Omega$. Because of a power failure,the magnetic field decays to $1 \, T$ in $10^{-3} \, s$. What is the total heat produced in her necklace in Joules?

$A$ rectangular coil of $100$ turns and size $0.1 \,m \times 0.05 \,m$ is placed perpendicular to a magnetic field of $0.1 \,T$. If the field drops to $0.05 \,T$ in $0.05 \,s$, the magnitude of the e.m.f. induced in the coil is (in $\,V$)

The north pole of a magnet is brought near a metallic ring. The direction of the induced current in the ring will be

Two coaxial coils carry current in the same direction. When the distance between the two coils is increased,the electric current in the coils will:

$A$ long solenoid with $15$ turns per $cm$ has a small loop of area $2.0 \,cm^2$ placed inside the solenoid normal to its axis. If the current carried by the solenoid changes steadily from $2.0 \,A$ to $4.0 \,A$ in $0.1 \,s$, the induced emf in the loop while the current is changing is nearly [Take $\pi=3.14$].