GCSE Physics Edexcel: Key Concepts and Units
SI (International System of Units) is the standard system for measurement used in science. Key SI units for physical quantities include:
Length: meter (m)
Mass: kilogram (kg)
Time: second (s)
Electric current: ampere (A)
Temperature: kelvin (K)
Amount of substance: mole (mol)
Luminous intensity: candela (cd)
Understanding prefixes for multiples and sub-multiples is crucial for converting between units:
Giga (G): 109
Mega (M): 106
Kilo (k): 103
Centi (c): 10-2
Milli (m): 10-3
Micro (μ): 10-6
Nano (n): 10-9
Conversion between different units is often required, particularly time units:
Hours to seconds: 1 hour = 3600 seconds
Example: 3 hours = 3×3600=10800 seconds
Using significant figures and standard form ensures precision and clarity:
Significant Figures: Used to represent the precision of a measurement.
Standard Form: Expressing numbers as a product of a number between 1 and 10 and a power of 10.
Example: 4500=4.5×103
Precision and accuracy in measurements.
Understanding of errors and how to minimize them.
Scalars: Quantities with magnitude only (e.g., mass, time).
Vectors: Quantities with both magnitude and direction (e.g., velocity, force).
Newton's Laws of Motion.
Equations of motion and their applications.
Different forms of energy and energy transfer.
Conservation of energy principle.
Characteristics of waves: amplitude, wavelength, frequency, and speed.
Types of waves: transverse and longitudinal.
Unit Conversion:
Convert 5 kilometers to meters.
Solution: 5 km=5×1000=5000m
Significant Figures:
Represent the number 0.00456 in 2 significant figures.
Solution: 0.0046
Standard Form:
Express the number 0.000789 in standard form.
Solution: 7.89×10-4
SI (International System of Units) is the standard system for measurement used in science. Key SI units for physical quantities include:
Length: meter (m)
Mass: kilogram (kg)
Time: second (s)
Electric current: ampere (A)
Temperature: kelvin (K)
Amount of substance: mole (mol)
Luminous intensity: candela (cd)
Understanding prefixes for multiples and sub-multiples is crucial for converting between units:
Giga (G): 109
Mega (M): 106
Kilo (k): 103
Centi (c): 10-2
Milli (m): 10-3
Micro (μ): 10-6
Nano (n): 10-9
Conversion between different units is often required, particularly time units:
Hours to seconds: 1 hour = 3600 seconds
Example: 3 hours = 3×3600=10800 seconds
Using significant figures and standard form ensures precision and clarity:
Significant Figures: Used to represent the precision of a measurement.
Standard Form: Expressing numbers as a product of a number between 1 and 10 and a power of 10.
Example: 4500=4.5×103
Precision and accuracy in measurements.
Understanding of errors and how to minimize them.
Scalars: Quantities with magnitude only (e.g., mass, time).
Vectors: Quantities with both magnitude and direction (e.g., velocity, force).
Newton's Laws of Motion.
Equations of motion and their applications.
Different forms of energy and energy transfer.
Conservation of energy principle.
Characteristics of waves: amplitude, wavelength, frequency, and speed.
Types of waves: transverse and longitudinal.
Unit Conversion:
Convert 5 kilometers to meters.
Solution: 5 km=5×1000=5000m
Significant Figures:
Represent the number 0.00456 in 2 significant figures.
Solution: 0.0046
Standard Form:
Express the number 0.000789 in standard form.
Solution: 7.89×10-4
