Explanation: Dipole moment p = q × d, where d is the distance between the charges.
A Denser to rarer medium
B Rarer to denser medium
C Vacuum to glass
D Air to water
Explanation: Total internal reflection occurs when light travels from a denser to a rarer medium at an angle greater than the critical angle.
A 10 cm
B 20 cm
C 40 cm
D 80 cm
Explanation: R = 2f = 2 × 20 = 40 cm
Explanation: Three geostationary satellites, spaced 120° apart, can cover most of the Earth\'s surface.
A Reflection
B Refraction
C Scattering
D Diffraction
Explanation: The sky appears blue due to Rayleigh scattering of sunlight by atmospheric molecules, which scatter shorter (blue) wavelengths more.
A √60 m/s
B √30 m/s
C √20 m/s
D 10 m/s
Explanation: By energy conservation: mgh = ½mv² → v = √(2gh) = √(2×10×3) = √60 m/s
A 9 N
B 18 N
C 27 N
D 36 N
Explanation: F = mv²/r = 2 × 36/4 = 72/4 = 18 N
A Isobaric
B Isothermal
C Adiabatic
D Isochoric
Explanation: In an adiabatic process, there is no heat exchange (Q = 0) between the system and surroundings.
A Volume only
B Pressure only
C Temperature only
D Both volume and pressure
Explanation: For an ideal gas, internal energy is a function of temperature only (U = f(T)).
Explanation: η = 1 - T₂/T₁ = 1 - 300/500 = 1 - 0.6 = 0.4 = 40%
A Hertz
B Decibel
C Bel
D Newton
Explanation: Frequency is measured in Hertz (Hz), where 1 Hz = 1 cycle per second
Explanation: Component along plane = W sin θ = W sin 30° = W × ½ = W/2
A Equal to weight of body
B Equal to weight of fluid displaced
C Equal to volume of body
D Zero
Explanation: By Archimedes\' principle, buoyant force equals the weight of the fluid displaced by the body.
A Voltage
B Current
C Power
D Resistance
Explanation: In series combination, the same current flows through all resistors.
A Maximum
B Minimum
C Zero
D Positive
Explanation: Centripetal force is always perpendicular to the velocity, so work = Fd cos 90° = 0
A 5/4 m/s²
B 1.25 m/s²
C 7 m/s²
D Both A and B
Explanation: Resultant = √(3²+4²) = 5 N. a = F/m = 5/4 = 1.25 m/s²
A Doubles
B Halves
C Remains same
D Quadruples
Explanation: v = fλ. If λ doubles and f is constant, v also doubles.
A 0.1 s
B 0.01 s
C 1 s
D 10 s
Explanation: Persistence of hearing is approximately 0.1 seconds, which is why we hear continuous sound.
A Virtual and erect
B Real and inverted
C Virtual and inverted
D Same size as object
Explanation: For an object beyond C in a concave mirror, the image is real, inverted, and diminished.
A 1 A
B 10 A
C √10 A
D 0.1 A
Explanation: P = I²R → 10 = I² × 10 → I² = 1 → I = 1 A