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#	Question	Subject and topic	Difficulty
101	In a purely inductive AC circuit, the current:	Physics Alternating current	Medium
102	As the frequency of the AC supply increases, the reactance of a capacitor:	Physics Alternating current	Hard
103	A series LCR circuit has L = 0.1 H and C = 10 μF. Its resonant frequency is about:	Physics Resonance and power in AC circuits	Medium
104	At resonance in a series LCR circuit, the impedance is:	Physics Resonance and power in AC circuits	Easy
105	The power factor of a purely inductive circuit is:	Physics Resonance and power in AC circuits	Easy
106	A series circuit with R = 30 Ω and Z = 50 Ω is connected to a 200 V (rms) supply. The average power consumed …	Physics Resonance and power in AC circuits	Medium
107	A choke coil is preferred to a resistor for reducing current in AC circuits because the choke:	Physics Resonance and power in AC circuits	Hard
108	A transformer has 200 turns in the primary and 1000 turns in the secondary. If the primary voltage is 220 V A…	Physics AC generator and transformer	Easy
109	An ideal step-down transformer gives 11 V and 4 A from a 220 V supply. The primary current is:	Physics AC generator and transformer	Medium
110	A coil of 100 turns and area 0.02 m² rotates at 50 revolutions per second in a field of 0.1 T. The peak emf i…	Physics AC generator and transformer	Hard
111	A transformer works on the principle of:	Physics AC generator and transformer	Easy
112	In an AC generator, the induced emf in the rotating coil is maximum when the plane of the coil is:	Physics AC generator and transformer	Medium
113	Maxwell's displacement current through a surface is given by:	Physics Displacement current	Easy
114	A parallel-plate capacitor is being charged, and the current in the connecting wires is 1.5 A. What is the di…	Physics Displacement current	Easy
115	The voltage across a 2 μF capacitor increases at a steady rate of 5000 V/s. What is the displacement current …	Physics Displacement current	Medium
116	In a plane electromagnetic wave in vacuum, the peak electric field is 6 V/m. What is the peak magnetic field?	Physics Displacement current	Medium
117	A plane electromagnetic wave travels along the +x axis and its electric field oscillates along the y axis. Al…	Physics Displacement current	Hard
118	Which electromagnetic radiation has the shortest wavelength?	Physics Electromagnetic spectrum	Easy
119	Radar systems used for aircraft navigation mainly use:	Physics Electromagnetic spectrum	Easy
120	An FM station broadcasts at 100 MHz. What is the wavelength of its waves in air?	Physics Electromagnetic spectrum	Medium
121	The ozone layer in the upper atmosphere protects living things mainly by absorbing:	Physics Electromagnetic spectrum	Medium
122	An electromagnetic wave has a frequency of 10 GHz. What are its wavelength and the band it belongs to?	Physics Electromagnetic spectrum	Hard
123	A spherical mirror has a radius of curvature of 24 cm. What is the magnitude of its focal length?	Physics Reflection by spherical mirrors	Easy
124	The image formed by a convex mirror of a real object is always:	Physics Reflection by spherical mirrors	Easy
125	An object is placed 20 cm in front of a concave mirror of focal length 15 cm. Where is the image and what is …	Physics Reflection by spherical mirrors	Medium
126	An object is placed 20 cm in front of a convex mirror of radius of curvature 40 cm. Where is the image?	Physics Reflection by spherical mirrors	Medium
127	A person stands 10 cm from a concave shaving mirror of focal length 15 cm. Which description of the image is …	Physics Reflection by spherical mirrors	Hard
128	The working of an optical fibre is based on:	Physics Refraction and total internal reflection	Easy
129	A water tank is 12 cm deep. Viewed from directly above, how deep does it appear? (Refractive index of water =…	Physics Refraction and total internal reflection	Easy
130	What is the critical angle for light going from a medium of refractive index √2 into air?	Physics Refraction and total internal reflection	Medium
131	Diamond sparkles more than glass cut to the same shape mainly because diamond has:	Physics Refraction and total internal reflection	Medium
132	A point object in air is 30 cm from the convex surface of a large glass block (n = 1.5). The radius of curvat…	Physics Refraction and total internal reflection	Hard
133	What is the power of a concave lens of focal length 25 cm?	Physics Lenses	Easy
134	An object is placed 30 cm in front of a convex lens of focal length 20 cm. What are the image distance and ma…	Physics Lenses	Medium
135	An equiconvex glass lens (n = 1.5) has both radii of curvature equal to 20 cm. What is its focal length?	Physics Lenses	Medium
136	Two thin lenses of power +5 D and –3 D are placed in contact. What is the focal length of the combination?	Physics Lenses	Medium
137	A glass convex lens (n = 1.5) has a focal length of 20 cm in air. What is its focal length when fully immerse…	Physics Lenses	Hard
138	A thin prism of angle 5° is made of glass of refractive index 1.5. What is its deviation of a ray?	Physics Prism	Easy
139	When white light passes through a glass prism, which colour is deviated the most?	Physics Prism	Easy
140	An equilateral glass prism gives a minimum deviation of 30°. What is the refractive index of the glass?	Physics Prism	Medium
141	A ray passes through an equilateral prism at minimum deviation. What is the angle of refraction at the first …	Physics Prism	Medium
142	A thin prism of angle 6° has refractive indices 1.66 for violet and 1.64 for red. What is the angular dispers…	Physics Prism	Hard
143	Why does the objective of an astronomical telescope have a large aperture?	Physics Optical instruments	Easy
144	A convex lens of focal length 5 cm is used as a simple microscope with the image formed at the near point (25…	Physics Optical instruments	Easy
145	An astronomical telescope has an objective of focal length 100 cm and an eyepiece of focal length 5 cm. In no…	Physics Optical instruments	Medium
146	A compound microscope has an objective of focal length 1 cm, an eyepiece of focal length 2.5 cm and a tube le…	Physics Optical instruments	Medium
147	A telescope in normal adjustment has a magnifying power of 25 and a tube length of 52 cm. What are the focal …	Physics Optical instruments	Hard
148	According to Huygens' principle, each point on a wavefront:	Physics Wave optics	Easy
149	Two coherent light waves reach a point with a path difference of 3λ/2. What is observed there?	Physics Wave optics	Easy
150	In Young's double-slit experiment, λ = 600 nm, slit separation 0.3 mm and screen distance 1.5 m. What is the …	Physics Wave optics	Medium