Engineering Questions — Physics
155 solved questions with detailed explanations
Q.40. A thin convex lens and a thin concave lens are kept in contact and are co-axial. Which of the following statements is correct for this combination of two lenses?
Q.29. Two blocks (P and Q) with respectively masses 2 kg and 1.5 kg are joined by a massless thread. These blocks are mounted on a frictionless pulley which is fixed on the edge of a cube (S), as show
Q.43. A large drum having radius R is spinning around its axis with angular velocity , as shown in figure. The minimum value of so that a body of mass M remains stuck to the inner wall of the drum, t
Q.26. The density of a uniform cylinder is determined by measuring its mass , length and diameter . The measured values of and are , and , respectively. Calculated percentage fractional error in
Q.28. At t = 0, a body of mass 100 g starts moving under the influence of a force N. After 2s its position is m . The ratio x : y is
Q.40. A magnetic field vector in an electromagnetic wave is represented by, . Its associated electric field vector is
Q.37. Under steady state condition the potential difference across the capacitor in the circuit is V.
Q.41. Two point charges q₁ = 3µC and q₂=-4µC are placed at points (2\hat{i}+3\hat{j}+3\hat{k}) and (\hat{i}+\hat{j}+\hat{k}) respectively. Force on charge q₂ is N. (Take \frac{1}{4\pi \epsilon_0} = 9×
Q.43. An electromagnetic wave travelling in x-direction is described by field equation . If the electron is restricted to move in y-direction only with speed of then ratio of maximum electric and mag
Q.31. The two projectiles are projected with the same initial velocities at the 15° and 30° with respect to the horizontal. The ratio of their ranges is 1: x. The value of x is
Q.37. A voltmeter with internal resistance of can be used to measure upto 20 V. In order to increase its measuring range to 30 V, the required modification is to ________
Q.33. The position of center of mass of three masses 2 kg, 3 kg and 15 kg placed with respect to mid point (p) of normal bisector, as shown in the figure is ________.
Q.26. Consider two identical metallic spheres of radius R each having charge Q and mass m. Their centers have an initial separation of 4R. Both the spheres are given an initial speed of u towards each
Q.36. In interference experiment the path difference between two interfering waves at a point A on the screen is , where is the wavelength of these waves, and at another point B the path difference i
Q.29. A gas balloon is going up with a constant velocity of 10 m/s. When this balloon reached a height of 75 m, a stone is dropped from it and balloon keeps moving up with the same velocity. The heigh
Q.47. An unpolarized light of intensity I passes through polarizer and then through a certain optically active solution and finally it goes to analyser. If the angle between analyser and polariser is
Q.44. Two radioactive substances A and B of mass numbers 200 and 212 respectively, shows spontaneous α-decay with same Q value of 1 MeV. The ratio of energies of α-rays produced by A and B is
Q.39. The maximum rated power of the LED is 2 mW and it is used in the circuit with input voltage of 5 V as shown in the figure below. The current through resistance is 0.5 mA. The minimum value of t
Q.41. The energy of an electron in an orbit of the Bohr's atom is eV where is the ground state energy. If L is the angular momentum of the electron in this orbit and h is the Planck's constant, then
Q.46. A copper wire of length 3 m is stretched by 3 mm by applying an external force. The volume of the wire is m³. The elastic potential energy stored in the wire in stretched condition would be J.