Physics Basic Concepts Practice Questions

Speed has only magnitude, no direction. Velocity, force, displacement are vectors.

Standard value of g is 9.8 m/s² or approximately 10 m/s²

Newton’s Third Law: For every action, there is an equal and opposite reaction

Work = Force × Distance, SI unit is Joule (J). 1 J = 1 N·m

Speed of light in vacuum is 3×10⁸ m/s, highest in universe

Power = Work/Time, SI unit is Watt (W). 1 W = 1 J/s

Barometer measures atmospheric pressure. Aneroid and mercury barometers are common types

SI unit of electric current is Ampere (A)

Ohm’s Law: V = IR, Voltage = Current × Resistance

Speed of sound in air at 20°C is approximately 343 m/s or 1235 km/h

Red light has longest wavelength (~700 nm), violet has shortest (~400 nm)

Frequency measured in Hertz (Hz). 1 Hz = 1 cycle per second

Concave mirror converges light to produce powerful beam

Pascal’s Law: Pressure applied to enclosed fluid transmitted equally

Copper is excellent conductor due to free electrons

SI unit of temperature is Kelvin (K). 0°C = 273.15 K

Myopia (nearsightedness) corrected by concave (diverging) lens

Escape velocity from Earth is 11.2 km/s or 40,320 km/h

Action (pushing water back) = Reaction (moving forward)

Pressure = Force/Area, SI unit Pascal (Pa). 1 Pa = 1 N/m²

Generator works on electromagnetic induction

Plane mirror has infinite focal length, forms virtual image

Rayleigh scattering: Blue light scattered more by air molecules

SI unit of charge is Coulomb (C). 1 C = charge of 6.24×10¹⁸ electrons

Silver has highest conductivity, followed by copper, gold, aluminum

Rocket expels gas backward (action), moves forward (reaction)

Ammeter measures current, connected in series

SI unit of luminous intensity is Candela (cd)

Convex lens converges light, magnifies objects

1 HP = 746 watts (British), metric HP = 735.5 W

First Law of Thermodynamics

Momentum = mass × velocity, unit kg·m/s

Convex mirror gives wider field of view, forms diminished image

Human hearing range: 20 Hz (infrasonic) to 20 kHz (ultrasonic)

Rainbow formed by refraction, dispersion, and internal reflection in water droplets

Resistance measured in Ohms (Ω), R = V/I

Capacitor stores charge, unit Farad

Water boils at 100°C (373 K) at 1 atm pressure

Archimedes Principle: Buoyant force equals weight of displaced fluid

Wavelength measured in meters (m), often nanometers for light

Violet has highest frequency (~750 THz), shortest wavelength

Power of lens = 1/focal length (in meters), unit Dioptre (D)

Thermometer measures temperature

SI unit of magnetic flux density is Tesla (T)

Boyle’s Law: P₁V₁ = P₂V₂ at constant temperature

Speed of light c = 299,792,458 m/s ≈ 3×10⁸ m/s

Electric motor works on Lorentz force

Ice melts at 0°C (273 K) at standard pressure

Stretched bow has elastic potential energy