Which of the following physical quantities has neither dimensions nor unit?
Point masses of 1,2,3 and 4 kg are lying at the points (0, 0, 0), (2 , 0, 0), (0, 3 , 0) an d ( - 2 , - 2, 0) respectively. The moment of inertia of this system about X-axis will be
1 Crore+ students have signed up on EduRev. Have you? Download the App |
A man wants to reach point B on the opposite bank of a river flowing at a speed as shown in figure. What minimum speed relative to water should the man have so that he can reach point B?
A bar magnet of magnetic moment is placed .in the magnetic field The torque acting on the magnet is
A stone of mass 1 kg tied to a light inextensible string of length L= 10/3 is whirling in a circular path of radius D in vertical plane. If the ratio of the maximum tension to the minimum tension in the string is 2, what is the speed of stone at the highest point of the circle?
(Take, g = 10 ms-2)
A simple pendulum is executing simple harmonic motion with a time period T. If the length of the pendulum is increased by 21% then the increase in the time period of the pendulum due to increased length is
A block of mass 10 kg, moving in x-direction with a constant speed of 10ms-1, is subjected to a retarding force F = 0.1 x J/m during its travel from x = 20m to 30. Its final KE will be
A triangular block of mass M with angles 30°, 60° and 90° rest with its 30° - 90° side on a horizontal table. A cubical block of mass m rests on 60° - 30° side. The acceleration which M must have relative to the table to keep m stationary relative to the triangular block is (assuming frictionless contact)
A round disc of moment of inertia I2 about its axis perpendicular to its plane and passing through its centre is placed over another disc of moment of inertia I1 rotating with an angular velocity ω about the same axis. The final angular velocity of the combination of discs is
A network of six identical capacitors, each of capacitance C is made as shown in the figure. The equivalent capacitance between points A and B is
The moon's radius is 1/4 that of the earth and its mass is 1/80 times that of the earth. If g represents the acceleration due to gravity on the surface of the earth, then on the surface of the moon its value is
If R is universal gas constant, the amount of heat needed to raise the temperature of 2 moles of an ideal monoatomic gas from 273 K to 373 K, when no work is done, is
If λm denotes the wavelength at which the radiative emission from a black body at a temperature T K is maximum, then
A wheel with ten metallic spokes each 0.50m long is rotated with a speed of 120 rev/min in a plane normal to the ea rth’s magnetic field at the place. If the magnitude of the field is 0.40 G, the induced emf between the axle and the rim of the wheel is equal to
An alternating voltage V = 30 sin 50 t + 40 cos 50 t is applied to a resistor of resistance 10Ω. The rms value of current through resistor is
A spool is pulled horizontally by two equal and opposite forces on rough surface. The correct statement is:
4 m3 of water is to be pumped to a height of 20 m and forced into a reservoir at a pressure of 2 x 105 N/m2. The work done by the motor is (External pressure = 10s N/m2)
Two bodies of masses 10 kg and 100 kg are separated by a distance of 2m ( G = 6.67 x 10-11 Nm2 kg-2). The gravitational potential at the mid point on the line joining the two is
A wave travelling in positive x-direction with A = 0.2 m, velocity = 3 6 0 ms-1 and λ = 60 m, then correct exppression for the wave is
A solid body rotates about a stationary axis, so that its angular velocity depends on the rotational angle φ as ω = ω0 - Kφ Where ω0 and k are positive constants. At the moment t = 0, φ = 0, the time dependence of rotation angle is
A, B and C are three points in a uniform electric field. The electric potential is
A 500 W heating unit is designed to operate on a 115 V line. If the line voltage drops to 110 V line, the percentage drop in heat output will be
Four charges equal to -Q are placed at the four corners of a square and a charge q is at its centre.
If the system is in equilibrium the value of q is
When the current changes from + 2 A to - 2 A in 0 .0 5 s, an emf of 8 V is induced in a coil. The coefficient of self-induction of the coil is
A bag of mass M hangs by a long thread and a bullet (mass m) comes horizontally with velocity V and gets caught in the bag. Then for the combined (bag + bullet) system
In an electromagnetic wave, the electric and magnetic, fields are 100 Vm-1 and 0.265 Am-1. The maximum energy flow is
The electric potential V(x) in a region around the origin is given by V(x) = 4x2 volts. The electric charge enclosed in a cube of 1 m side with its centre at the origin is (in coulmb)
A mixture of light consisting of wavelength 590 nm and an unknown wavelength illuminates Young's double slit and gives rise to two overlapping interference patterns on the screen. The central maximum of both light coincide. Further, it is observed that the third brigth fringe is known light coincides with the 4th bright fringe of unknown light. From this idea, the wavelength of unknown light is