Physics

In the colour coding system of carbon resistors, the tolerance (in %) shown by gold band is ____.

A radioactive sample decays with a constant of (1/3)logₑ2 s⁻¹. If initially there are 200 nuclei present, find the number of nuclei decayed during the first 9 seconds.

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.

If the molar specific heat at constant pressure for a polyatomic non-linear gas is x and the molar specific heat at constant volume for a diatomic gas is y, find the value of x y

A plank of mass 5 kg in kept on a smooth surface. A block of 1 kg is kept on it and is given a velcoity of 12 m/s. There is friction between the block and the plank. Assuming the plank to be very long, find the magnitude of work done (in Joules) by friction on block till the relative sliding between them stops.

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.

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)

Three thin rods of mass m and length a each are joined to form a triangle ABC in vertical plane. The triangle is pivoted at the vertex A such that it can rotate in the vertical plane. It is released from rest when the side AB is horizontal as shown. As the triangle rotates, the maximum velocity of the vertex B, VMAX , is given by:

A car goes on a circular horizontal road of radius 100 m. What should be the minimum coefficient of friction between the tyres and the road so that it completes the circle with velocity 10 m/s without slipping? (Take g = 10 m/s²)

Distance travelled by linear scale of screw gauge during two full rotation of circular scale is 1mm and circular scale has 50 divisions. In an experiment to measure thickness of a plate, six divisions of main scale are clearly visible and 28th division of circular scale coincides with reference line. Moreover when studs touch each other, zero of circular scale lies 4 division below the reference line, thickness of the plate will be: