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GCSE Physics Edexcel: Key Concepts and Units
1.1 SI Units for Physical Quantities
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)
1.2 Multiples and Sub-Multiples of Units
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
1.3 Converting Between Units
Conversion between different units is often required, particularly time units:
Hours to seconds: 1 hour = 3600 seconds
Example: 3 hours = 3×3600=10800 seconds
1.4 Significant Figures and Standard Form
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
Summary Notes from Topic 1: Key Concepts in Physics
Measurement and Uncertainty
Precision and accuracy in measurements.
Understanding of errors and how to minimize them.
Scalars and Vectors
Scalars: Quantities with magnitude only (e.g., mass, time).
Vectors: Quantities with both magnitude and direction (e.g., velocity, force).
Forces and Motion
Newton's Laws of Motion.
Equations of motion and their applications.
Energy
Different forms of energy and energy transfer.
Conservation of energy principle.
Waves
Characteristics of waves: amplitude, wavelength, frequency, and speed.
Types of waves: transverse and longitudinal.
Practical Applications and Problem Solving
Example Problems:
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
GCSE Physics Edexcel: Key Concepts and Units
1.1 SI Units for Physical Quantities
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)
1.2 Multiples and Sub-Multiples of Units
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
1.3 Converting Between Units
Conversion between different units is often required, particularly time units:
Hours to seconds: 1 hour = 3600 seconds
Example: 3 hours = 3×3600=10800 seconds
1.4 Significant Figures and Standard Form
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
Summary Notes from Topic 1: Key Concepts in Physics
Measurement and Uncertainty
Precision and accuracy in measurements.
Understanding of errors and how to minimize them.
Scalars and Vectors
Scalars: Quantities with magnitude only (e.g., mass, time).
Vectors: Quantities with both magnitude and direction (e.g., velocity, force).
Forces and Motion
Newton's Laws of Motion.
Equations of motion and their applications.
Energy
Different forms of energy and energy transfer.
Conservation of energy principle.
Waves
Characteristics of waves: amplitude, wavelength, frequency, and speed.
Types of waves: transverse and longitudinal.
Practical Applications and Problem Solving
Example Problems:
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
