If the binding energy of an electron in a hydrogen atom is 13.6 eV, then the energy required to remove the electron from the first excited state of Li++ is
A particle is dropped from height 3R from surface of earth then velocity of particle at height R is (given R is radius of earth, g is acceleration due to gravity) :
A satellite of mass m, is orbiting around the earth at a distance r from centre of earth, if it is stopped suddenly the loss in total energy will be
A uniform cylinder of density σ and length L floats vertically completely immersed in two liquids with length L1 immersed in a liquid of density ρ1 and the remaining length L2 immersed in the other liquid of density ρ2 as shown in Fig. The ratio L1/L2 will be (ρ1 > ρ2) equal to
The K.E. and P.E. of a particle executing SHM with amplitude A will be equal when its displacement is:
An electric dipole of moment is placed at the origin along the X-axis. The electric field at a point P, whose position vector makess an angle θ with the X-axis, will make an angle φ with the X-axis, then φ is (α = tan−1(1/2 tanθ))
Two coils A and B, each of 10 turns and radius 20 cm, are held such that coil A lies in the vertical plane and coil B in the horizontal plane with their centres coinciding. What current should be passed through the coils so as to nullify the earth's magnetic field at their common centre? Horizontal component of earth's field = 0.314 × 10−4 T and angle of dip = 26.6°. Given tan 26.6° = 0.5
A cube of side 2 m is placed in front of a concave mirror of focal length 1 m with its face A at a distance of 3 m and face B at a distance of 5 m form the mirror. The distance between the images of faces A and B and heights of images of A and B are, respectively,
A point source of light is placed in front of a plane mirror as shown in the figure.
Determine the length of reflected path of light on its screen Σ.
An electromagnetic radiation given by
E = E0[sin(2πv1t) + sin(2πv2t)]
where v1 = 1.3 × 1015 Hz and v2 = 1.1 × 1015 Hz falls on a photocell whose work function is 2.0eV. Then the photoelectric current through the cell
On a particular day, the maximum frequency reflected from the ionosphere is 8MHz. On another day it was found to increase to 9MHz. The ratio of the maximum electron densities of the ionosphere on the two days is
A parallel plate air-filled capacitor has a capacitance of 2 μF . When it is half-filled with a dielectric of dielectric constant k = 3, its capacitance becomes
A coil having n turns and resistance RΩ is connected with a galvanometer of resistance 4RΩ. This combination is moved in time t seconds from a magnetic field W1 weber to W2 weber. The induced current in the circuit is
The ratio of the speed of sound in nitrogen gas to that in helium gas, at 300 K, is
A cannon on a level plain is aimed at an angle α above the horizontal and a shell is fired with a muzzle velocity v0 towards a vertical cliff, a distance R away. The height from the bottom at which the shell strikes the side walls of the cliff is
Directions: This question has Statement-I and Statement-II. Of the four choices given after the statements, choose the one that best describes the two statements.
Statement-I: Higher the range, greater is the resistance of ammeter.
Statement-II: To increase the range of ammeter, additional shunt needs to be used across it.
The two physical quantities among the following which don't have the same dimensions are
When a rubber band is stretched by a distance x, it exerts a restoring force of magnitude F = ax + bx2, where a and b are constants. The work done in stretching the unstretched rubber band by L is
Find the angular speed of the meter stick, when a person throws it such that the centre of the stick is moving with a speed of 10 m s-1 vertically upwards & left end of stick with a speed of 20 m s-1 vertically upwards.
The adjacent graph shows the extension (Δl) of a wire of lengthlm suspended from the top of a roof at one end and with a load W connected to the other end. If the cross-sectional area of the wire is 10-6 m2, then the Young's modulus of the material of the wire comes out to be 2 × 10Q N/m2. State the value of Q.
In an LCR series ac circuit, the voltage across each of the components L, C and R is 50 V. The voltage across the LC combination (in Volt) will be
In an experiment with sonometer, a tuning fork of frequency 256 Hz resonates with a length of 25 cm and another tuning fork resonates with a length of 16 cm. If tension of the string remains constant, the frequency (in Hz) of the second tuning fork is:
If the equilibrium constant for the reaction, 2SO2 + O2 ⇌ 2SO3 is 64 at 500 K, then the equilibrium constant for the reaction at the same temperature is
The tendency of BF3, BCl3 and BBr3 to behave as Lewis acid decreases in the sequence
Standard electrode potential data are useful for understanding the suitability of an oxidant in a redox titration. Some half cell reactions and their standard potentials are given below
MnO−4(aq) + 8H+(aq) + 5e− → Mn+2(aq) + 4H2O(l) ; E∘ = 1.51 V
Cr2O72−(aq) + 14H+(aq) + 6e− → 2Cr+3(aq) + 7H2O(l) ; E∘ = 1.38 V
Fe+3(aq) + e− → Fe+2 ; E0 = 0.77 V
Cl2(g) + 2e− → 2Cl−(aq) ; E0 = 1.40 V
Identify the only incorrect statement regarding the quantitative estimation of aqueous Fe(NO3)2
Which of the following orders is true regarding the basic nature of NH2 group?
Which of the following diseases is not caused by bacteria?
If PQ is a double ordinate of hyperbola such that OPQ is an equilateral triangle, O being the centre of the hyperbola, then the eccentricity e of the hyperbola satisfies
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