Class 12th

Two fixed long parallel horizontal rails, a distance 1 m apart are joined at one end by a resistance 1Ω . A rod AB of negligible resistance slides towards the resistance. A magnetic field of magnitude 4T perpendicular to the plane of rails exists. Find the current flowing (in Ampere) in the resistance, at an instant when the velocity of the rod is 2 m/s.

Two capacitros are fully charged by a battery as shown in the figure.

If the capacitors are disconnected from battery and plate 1 is connected to plate 4 & plate 2 to plate 3, then find the potential difference (in volts) across capacitors finally.

What is the final product (major) 'A' in the given reaction?

When monochromatic light of wavelength 620 nm is used to illuminate a metallic surface, the maximum kinetic energy of photoelectrons emitted is 1 eV. Find the maximum kinetic energy of photoelectron emitted (in eV) if a wavelength of 155 nm is used on the same metallic surface. (hc = 1240 eV-nm)

Phenol on reaction with dilute nitric acid, gives two products. Which method will be most efficient for large scale separation?

Al₂O₃ was leached with alkali to get X. The solution of X on passing of gas Y, forms Z. X, Y and Z respectively are:

What is the major product formed by HI on reaction with

Which of the following compound given pink colour on reaction with phthalic anhydride in conc. H₂SO₄ followed by treatment with NaOH?

The eutrophication of water body results in:

The product formed in the first step of the reaction of