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A galvanometer having a coil of resistance 30Ω need 20 mA of current for full-scale deflection. If a maximum current of 3 A is to be measured using this galvanometer, the resistance of the shunt to be added to the galvanometer should be $$\frac{30}{X}$$Ω.where X is Options
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A ball having kinetic energy KE, is projected at an angle of $$60^{\circ}$$ from the horizontal. What will be the kinetic energy of ball at the highest point of its flight ?
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Two charges $$7\mu c$$ and $$-4\mu c$$ are placed at (−7 cm, 0, 0) and (7 cm, 0, 0) respectively. Given, $$\epsilon_{\circ}=8.85\times 10^{-12}C^{2}m^{-2}$$, the electrostatic potential energy of the charge configuration is :
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Two point charges $$-4\mu c$$ and $$4\mu c$$, constituting an electric dipole, are placed at (−9, 0, 0)cm and (9, 0, 0)cm in a uniform electric field of strength $$10^{4}NC^{-1}$$. The work done on the dipole in rotating it from the equilibrium through $$180^{\circ}$$ is :
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A massless spring gets elongated by amount $$x_{1}$$ under a tension of 5 N . Its elongation is $$x_{2}$$ under the tension of 7 N . For the elongation of $$(5x_{1}-2x_{2})$$,the tension in the spring will be,
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Water of mass m gram is slowly heated to increase the temperature from $$T_{1}$$ to $$T_{2}$$ The change in entropy of the water, given specific heat of water is $$1Jkg^{-1}K^{-1}$$, is :
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Water flows in a horizontal pipe whose one end is closed with a valve. The reading of the pressure gauge attached to the pipe is $$P_{1}$$. The reading of the pressure gauge falls to $$P_{2}$$ when the valve is opened. The speed of water flowing in the pipe is proportional to
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A concave mirror of focal length $$f$$ in air is dipped in a liquid of refractive index $$\mu$$. Its focal length in the liquid will be:
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What is the current through the battery in the circuit shown below
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5 The refractive index of the material of a glass prism is $$\sqrt{3}$$. The angle of minimum deviation is equal to the angle of the prism. What is the angle of the prism?
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The width of one of the two slits in Young's double slit experiment is d while that of the other slit is $$x$$ d. If the ratio of the maximum to the minimum intensity in the interference pattern on the screen is 9:4 then what is the value of $$x$$ ? (Assume that the field strength varies according to the slit width.)
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Using the given P - V diagram, the work done by an ideal gas along the path ABCD is :
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A plane electromagnetic wave of frequency 20 MHz travels in free space along the +x direction. At a particular point in space and time, the electric field vector of the wave is $$E_{y}=9.3Vm^{-1}$$. Then, the magnetic field vector of the wave at that point is
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The equation of a transverse wave travelling along a string is $$y(x,t)=4.0\sin[20\times 10^{-3}x+600t]mm$$ where x is in mm and t is in second. The velocity of the wave is :
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Given below are two statements. One is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : The binding energy per nucleon is found to be practically independent of the atomic number A, for nuclei with mass numbers between 30 and 170. Reason (R): Nuclear force is long range. In the light of the above statements, choose the correct answer from the options given below :
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If a satellite orbiting the Earth is 9 times closer to the Earth than the Moon, what is the time period of rotation of the satellite? Given rotational time period of Moon =27 days and gravitational attraction between the satellite and the moon is neglected.
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A circular disk of radius R meter and mass M kg is rotating around the axis perpendicular to the disk. An external torque is applied to the disk such that $$\theta (t)=5t^{2}-8t$$, where $$\theta (t)$$ is the angular position of the rotating disc as a function of time t. How much power is delivered by the applied torque, when t = 2 s ?
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The energy of a system is given as $$E(t)=\alpha^{3}e^{-\beta t}$$, where t is the time and $$\beta= 0.3s^{-1}$$. The errors in the measurement of $$\alpha$$ and t are 1.2% and 1.6%, respectively. At t=5s,maximum percentage error in the energy is:
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Match List - I with List - II.
Choose the correct answer from the options given below :
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In photoelectric effect an em-wave is incident on a metal surface and electrons are ejected from the surface. If the work function of the metal is 2.14 eV and stopping potential is 2 V , what is the wavelength of the emwave ? (Given hc = 1242eVnm where h is the Planck's constant and c is the speed of light in vaccum.)
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A time varying potential difference is applied between the plates of a parallel plate capacitor of capacitance $$2.5\mu F$$. The dielectric constant of the medium between the capacitor plates is 1 . It produces an instantaneous displacement current of 0.25 mA in the intervening space between the capacitor plates, the magnitude of the rate of change of the potential difference will be _____$$Vs^{-1}$$.
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In a series LCR circuit, a resistor of 300Ω, a capacitor of 25 nF and an inductor of 100 mH are used. For maximum current in the circuit, the angular frequency of the ac source is _____$$\times 10^{4}\text{ radians }s^{-1}$$
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An air bubble of radius 1.0 mm is observed at a depth of 20 cm below the free surface of a liquid having surface tension $$0.095 J/m^{2}$$ and density $$10^{3}kg/m^{3}$$. The difference between pressure inside the bubble and atmospheric pressure is _____$$N/m^{2}.(\text{ take }g=10m/s^{2})$$
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A satellite of mass $$\frac{M}{2}$$ is revolving around earth in a circular orbit at a height of $$\frac{R}{3}$$ from earth surface. The angular momentum of the satellite is $$M\sqrt{\frac{GMR}{x}}$$.The value of $$x$$ is ______ , where M and R are the mass and radius of earth, respectively. ( G is the gravitational constant)
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At steady state the charge on the capacitor, as shown in the circuit below, is $$\mu C$$.
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