Which of the following salts does not give a flame test?

$A$ wire in the form of a square of side $a$ carries a current $i$. Then,the magnetic induction at the centre of the square is (Magnetic permeability of free space $= \mu_0$)

What will be the angular width of the central maxima in Fraunhofer diffraction when light of wavelength $6000 \, \mathring{A}$ is used and the slit width is $12 \times 10^{-5} \, cm$? (in $rad$)

According to the law of equipartition of energy,the molar specific heat of a diatomic gas at constant volume,where the molecule has one additional vibrational mode,is:

Which of the following halides is most acidic?

$A$ body of mass $5 \ kg$ starts from the origin with an initial velocity $u = 30 \hat{i} + 40 \hat{j} \ ms^{-1}$. When a constant force $F = -(\hat{i} + 5 \hat{j}) \ N$ acts on the body,the time in which the $y$-component of the velocity becomes zero is (in $s$)