Grade 10 Physics Vocabulary Flashcards (Myanmar Textbook)

Vocabulary flashcards covering key concepts and definitions from the Grade 10 Physics lecture notes, including units, motion, forces, energy, waves, light, electricity, magnetism, quantum physics, and astronomy.

Physical quantity

A quantity that can be measured and has a numerical magnitude and a unit.

Basic unit

A fundamental unit used as a reference for measuring a physical quantity.

Derived unit

A unit formed by combining basic (base) units.

SI base units

The seven fundamental SI units: metre (m), kilogram (kg), second (s), ampere (A), kelvin (K), mole (mol), candela (cd).

System of units

Different unit systems (FPS, CGS, MKS) with SI being the standard metric system.

Prefix (SI prefixes)

Multiples or submultiples of 10 used with units (e.g., kilo, milli, micro, nano).

British system (FPS)

Foot–Pound–Second system of units.

CGS system

Centimetre–Gram–Second system.

MKS system

Metre–Kilogram–Second system.

Scientific notation

Expressing numbers as a × 10^n, with the decimal moved to indicate n.

Physical quantity (example)

A measurable quantity such as length, mass, time, temperature.

Vector

A quantity with both magnitude and direction; represented by arrows or bold symbols.

Scalar

A quantity with only magnitude and no direction.

Displacement

The straight-line vector from the starting point to the end point.

Distance

The length of the path travelled; a scalar quantity.

Speed

Rate of motion; magnitude of velocity (how fast).

Velocity

Speed with a specified direction (rate of displacement).

Acceleration

Rate of change of velocity over time.

Resultant vector

The vector sum of two or more vectors.

Components

Projection of a vector along the x- and y-axes (e.g., x- and y-components).

Horizontal component

The x-component of a vector: A_x = A cos θ.

Vertical component

The y-component of a vector: A_y = A sin θ.

Instantaneous speed

Speed at a specific instant (time rate of change of distance).

Instantaneous velocity

Velocity at a specific instant (time rate of change of displacement).

Average speed

Total distance divided by total time.

Average velocity

Total displacement divided by total time.

Equation of motion (linear, constant acceleration)

Relationships among s, v, u, a for motion with constant acceleration; e.g., v = u + at.

Uniform motion

Motion with constant velocity; zero acceleration.

Constant acceleration

Velocity changes at a constant rate; acceleration is constant.

Inertia

Natural resistance of a body to changes in its state of motion.

Newton's first law

An object stays at rest or moves with constant velocity if net external force is zero.

Net external force

Vector sum of all external forces acting on a body.

Mass

A measure of the amount of matter; intrinsic inertia of a body.

Weight

The force of gravity acting on a body, w = m g; depends on location.

Acceleration due to gravity (g)

Constant acceleration of falling bodies near Earth's surface, ~9.8 m s^-2 downward.

Momentum

p = m v; a vector quantity representing motion; conserved in isolated systems.

Conservation of momentum

In an isolated system, total momentum before equals total momentum after a collision.

Archimedes' principle

Buoyant force equals the weight of the liquid displaced by a submerged object.

Buoyancy

Upward force on a body immersed in a fluid.

Density

ρ = m / V; mass per unit volume (kg/m^3 in SI).

Relative density (specific gravity)

Density of a substance divided by the density of water (dimensionless).

Hydrometer

Instrument to measure the density or relative density of liquids by buoyancy.

Pressure

Force per unit area; p = F / A; SI unit is pascal (Pa) = N/m^2.

Standard atmospheric pressure

1 atm ≈ 1.013 × 10^5 Pa (or 1013 hPa or 760 mm Hg).

Coefficient of linear expansion (α)

ΔL = α L ΔT; change in length per unit length per 1 K change in temperature.

Coefficient of area expansion

Change in area per unit area per degree change in temperature (β).

Coefficient of volume expansion

Change in volume per unit volume per degree change in temperature (γ).

Anomalous expansion of water

Water is most dense at 4°C; below/above this, density decreases with temperature.

Heat

Energy transfer between bodies due to temperature difference; energy in transit.

Temperature

A measure of hotness/coldness; not energy; measured by thermometers.

Thermometer

Instrument to measure temperature using thermometric properties.

Coefficient of expansion (summary)

α for length, β for area, γ for volume; describe how dimensions change with temperature.

Wave

A disturbance that transfers energy through a medium or space without transporting matter.

Transverse wave

Vibrations perpendicular to the direction of wave propagation.

Longitudinal wave

Vibrations parallel to the direction of wave propagation.

Frequency

Number of cycles per second; unit hertz (Hz).

Wavelength

Distance between consecutive crests (or troughs) of a wave.

Amplitude

Maximum displacement of particles in a wave from equilibrium.

Velocity of a wave

Speed at which a wave propagates; v = f λ.

Reflection

Bouncing of a wave at a boundary; angle of incidence equals angle of reflection.

Refraction

Change of direction of a wave as it crosses a boundary; speed and wavelength change.

Diffraction

Spreading of waves around obstacles or through gaps.

Speed of sound

Velocity at which sound waves travel in a medium; varies with medium and temperature.

Light sources (luminous vs non-luminous)

Luminous sources emit their own light; non-luminous objects reflect light.

Plane mirror

Flat mirror producing virtual, erect, same-size images located behind the mirror.

Curved mirrors (concave/convex)

Concave can form real or virtual images; convex always forms virtual images.

Focal length (f)

Distance from mirror to the focal point; relates to radius of curvature.

Radius of curvature (R)

Radius of the sphere of which the mirror is a part.

Magnetic field

Region around a magnet where magnetic effects can be detected.

Magnetic lines of force

Imaginary lines showing the pattern of a magnetic field.

North/South poles

Ends of a magnet where magnetic effects are concentrated; like poles repel, unlike attract.

Magnetisation

Process of making a material into a magnet (stroking or DC current).

Induced magnetism

Temporary magnetism induced in a material brought near a magnet.

Permanent magnet vs soft magnet

Permanent magnets retain magnetism; soft magnets are easily demagnetized.

Photon

Quantum of light energy; E = h f; photons carry energy proportional to frequency.

Planck constant (h)

h ≈ 6.626 × 10^-34 J s; relates energy and frequency for photons.

Blackbody radiation

Radiation emitted by a perfect absorber; intensity depends on temperature; Wien’s and Stefan–Boltzmann laws.

Atomic number (Z)

Number of protons (and electrons in a neutral atom); determines identity of the element.

Mass number (A)

Total number of protons and neutrons in the nucleus.

Isotope

Atoms with same Z but different A due to different neutron numbers.

Astronomical Unit (AU)

Mean distance between Earth and Sun, about 1.496 × 10^8 km.

Light year (ly)

Distance light travels in one year; ≈ 9.46 × 10^12 km.

Parsec (pc)

Distance corresponding to 1 arcsecond at 1 AU; ≈ 3.09 × 10^16 m.