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Water has been filled in a vertical capillary tube upto the top after closing its lower end by a finger Consider radius of capillary r = 1 mm, surface tension is 70 dyne/cm and g = 980 cm/sec2. Which of the option is correct when finger is removed?

If the gravitational acceleration at the surface of earth is g, then increase in potential energy in lifting an object of mass m from earth surface to a height equal to half of radius of earth from surface will be:

The length of a potentiometer wire is ?. A cell of emf E is balanced at a length ?/4 from the positive end of the wire. If the length of the wire is increased by ?/2, at what distance will the same cell give a balanced point? (Potentiometer battery is ideal)

The spectrum of a black body at two temperature 127°C and 527°C is shown in the figure. Let A1 and A2 be the areas under the two curves respectively. The value A_1/A_{2 is:}

A vernier caliper has 10 main scale divisions coinciding with 11 vernier scale divisions. 1 main scale division equals 5 mm. The least count of the device is

The dimensions of angular impulse is equal to

If a star emitting light of wavelength 500 nm is moving towards earth with a velocity of 1.5 ´ 106 m/s then the shift in the wavelength due to doppler’s effect will be:

Which of the following graph represents the damped oscillation motion?

When a metallic surface is illuminated with radiation of wavelength l, the stopping potential is V. If the same surface is illuminated with radiation of wavelength 2l, the stopping potential is  V . The threshold wavelength metallic surface is

The core of a transformer is laminated to reduce energy losses due to

The force required to stretch a steel wire of cross section 4 cm2 to 1.02 times its length would be (Y = 2*10¹¹ N m^–2)

Consider a uniform square plate of side ‘a’ and mass ‘m’. The moment of inertia of this plate about an axis perpendicular to its plane and passing through one of its corners is:

If wavelength corresponding to 2^nd line of Lyman series is l, then the wavelength corresponding to last line of Balmer series will be:

For the transistor circuit as shown. If b = 100, voltage drop between emitter and base is 0.7 V then value of VCE will be:-

A nuclear fusion reaction is given by   If atomic mass of He is 4.0026 amu and that of O is 15.9994 amu then the Q-value of the reaction will be approximately

Centre of mass for a uniform semi-circular ring will be at (from centre)