Class 12th

In a series LR circuit, power of 400 W is dissipated from a source of 250 V, 50 Hz. The power factor of the circuit is 0.8 . In order to bring the power factor to unity, a capacitor of value C is added in series to the L and R. Taking the value of C as (n/3π) μF, then value of ' n ' is

250 mL of a waste solution obtained from the workshop of a goldsmith contains 0.1M AgNO3 and 0.1M AuCl. The solution was electrolyzed at 2 V by passing a current of 1 A for 15 minutes. The metal/metals electrodeposited will be : (E°Ag+/Ag = 0.8 V, E°Au+/Au = 1.69 V)

The processes of calcination and roasting in metallurgical industries, respectively, can lead to:

The Crystal Field Stabilization Energy (CFSE) of [CoF₃(H₂O)₃](Δo < P) is :

A Young's double-slit experiment is performed using monochromatic light of wavelength λ. The intensity of light at a point on the screen, where the path difference is λ, is K units. The intensity of the light at a point where the path difference is λ/6 is given by nK/12, where ' n ' is an integer. The value of ' n ' is

Orange light of wavelength 6000 * 10^-10 m illuminates a single slit of width 0.6 * 10^-4 m. the maximum possible number of diffraction minima produced on both sides of the central maximum is

Four resistance 40Ω, 60Ω, 90Ω, and 110Ω make the arms of a quadrilateral ABCD. Across AC is a battery of emf 40 V and internal resistance negligible. The potential difference across BD in V is

The out put characteristics of a transistor is shown in the figure. When VCE is 10 V and Ic = 4.0 mA, then value of βac is

The distance between an object and a screen is 100 cm. A lens can produce real image of the object on the screen for two different positions between the screen and the object. The distance between these two positions is 40 cm. If the power of the lens is close to (N/100) D where N is an integer, the value of N is

Match the following: