RIDDLES — INTRODUCTION TO PHYSICS AND MATTER
Physics & Mathematical Tools
Riddle 1: I am a scientific discipline, not a single force. I study matter, energy and the fundamental forces of nature. My name originates from the Latin word "physica", meaning "natural thing". I seek to understand the physical universe through observation, experimentation and mathematical modelling. Who am I?
ANSWER: Physics
Riddle 2: I am a set of three ratios, not a single number. I relate the angles of a right triangle to the lengths of its sides. Sine, cosine and tangent are my three members. Navigation relies on me to determine direction and position. Who am I?
ANSWER: Trigonometric Ratios
Riddle 3: I am a theorem, not a triangle myself. I state that in a right triangle, the square of the hypotenuse equals the sum of the squares of the other two sides. I am written as a² + b² = c². Staircase design and construction rely on me. Who am I?
ANSWER: Pythagoras' Theorem
Riddle 4: I am a rule relating the sides of any triangle to the sines of its angles. I am useful for solving triangles when two angles and one side, or two sides and one angle, are known. Architects use me to determine the lengths of the sides of irregularly shaped buildings. Who am I?
ANSWER: Sine Rule
Riddle 5: I am a rule relating the lengths of the sides of a triangle to the cosine of one of its angles. I am useful for solving triangles when all three sides, or two sides and the included angle, are known. Mechanical engineers use me to calculate forces and angles in gears and pulleys. Who am I?
ANSWER: Cosine Rule
Riddle 6: I am a set of rules, not a single number. I govern repeated multiplication of the same number by itself. Multiplying same-base powers by adding their exponents is one of my rules. Scientists rely on me to represent very large or very small numbers using exponential notation. Who am I?
ANSWER: Indices (Laws of Indices)
Quantities and Units
Riddle 7: I am a characteristic or property that can be measured or quantified. I come in two types, fundamental and derived. Every measurement made in physics concerns one of me. Who am I?
ANSWER: Physical Quantity
Riddle 8: I am an independent physical quantity. I cannot be defined in terms of other physical quantities. Length, mass, time, temperature, electric current, amount of substance and luminous intensity are my seven examples. Who am I?
ANSWER: Fundamental Quantity
Riddle 9: I am a physical quantity derived from one or more fundamental quantities through mathematical combination. Force, volume, pressure, energy and velocity are all examples of me. I am built upon fundamental quantities, not independent of them. Who am I?
ANSWER: Derived Quantity
Riddle 10: I am a standard unit of measurement for a fundamental quantity. I am defined independently and cannot be derived from other units. The metre, kilogram and second are examples of me. The International System of Units recognises seven of me. Who am I?
ANSWER: Basic (Fundamental) Units
Riddle 11: I am a unit of measurement created by combining fundamental units according to specific mathematical relationships. The newton and the pascal are examples of me. I measure quantities derived from the basic or fundamental quantities. Who am I?
ANSWER: Derived Units
Dimensions
Riddle 12: I am an expression that relates a physical quantity to the fundamental quantities. I am represented using square brackets. The dimension of length is written as [L]. Who am I?
ANSWER: Dimension (of a Physical Quantity)
Riddle 13: I am a method used in physics, not a single equation. I check the consistency of equations, convert units and derive relationships between physical quantities. I do not account for numerical constants. Who am I?
ANSWER: Dimensional Analysis
Errors and Measuring Instruments
Riddle 14: I am a property of a measuring instrument, not the instrument itself. I am the smallest value an instrument can accurately measure. I help minimise uncertainties and errors by aiding in selecting appropriate instruments. Who am I?
ANSWER: Least Count
Riddle 15: I am a type of measurement error. I consistently deviate from the true value in the same direction. I often arise due to zero errors in equipment or errors in the scales on the equipment. Who am I?
ANSWER: Systematic Error
Riddle 16: I am also a type of measurement error, but an unpredictable one. I am caused by the person carrying out the measuring or by experimental conditions. Repeating a reading several times and averaging can reduce me. Who am I?
ANSWER: Random Error
Riddle 17: I am a type of measurement error caused by incorrect eye position. I occur when the eyes are not aligned properly with a measuring scale while taking a reading. The meniscus of a measuring cylinder is a common place where I appear. Who am I?
ANSWER: Parallax Error
Riddle 18: I describe how consistent or reproducible a set of measurements is. I show how closely measurements cluster around a central value. A greater number of decimal places in a recorded measurement usually reflects more of me. Who am I?
ANSWER: Precision
Riddle 19: I describe the closeness of measured values to the true value. I am influenced by the precision of the measuring tool, environmental conditions, human error and calibration. A reading can have precision without possessing me. Who am I?
ANSWER: Accuracy
Riddle 20: I am a measuring instrument, not a rule. I measure internal and external dimensions and depths. My least count is typically 0.02 mm. Misreading my scale by not aligning the zero mark properly is a common error made when using me. Who am I?
ANSWER: Vernier Calliper
Riddle 21: I am a measuring instrument known for very fine precision. Applying excessive force with my ratchet can compress the object being measured, causing an error. I should be used gently to ensure consistent and accurate measurements. Who am I?
ANSWER: Micrometer Screw Gauge
Riddle 22: I am an electrical measuring instrument, not a resistor. I must be connected in parallel with the component being measured, never in series. Connecting me incorrectly can alter the circuit and provide incorrect readings. Who am I?
ANSWER: Voltmeter
Riddle 23: I am also an electrical measuring instrument, but I must be connected in series with a circuit, never in parallel. Connecting me incorrectly can damage the meter or the circuit. Who am I?
ANSWER: Ammeter
Scientific Notation
Riddle 24: I am a concise and standardised way to express very large or very small numbers. I consist of a coefficient between 1 and 10 multiplied by a power of 10. The speed of light, 3 × 10&sup8; m/s, is often written using me. Who am I?
ANSWER: Scientific Notation
Riddle 25: I am a specifier attached to units of measurement to indicate multiples or fractions of a unit. Kilo, mega, centi and nano are all examples of me. I am commonly used to form units of various sizes, such as the kilogram or the nanometre. Who am I?
ANSWER: Unit Prefix
Scalars and Vectors
Riddle 26: I am a type of physical quantity described solely by magnitude. I have no direction associated with me. Distance, speed, time and temperature are all examples of me. Who am I?
ANSWER: Scalar Quantity
Riddle 27: I am also a type of physical quantity, but I have both magnitude and direction. Velocity, displacement, force and acceleration are all examples of me. I am represented graphically by an arrow. Who am I?
ANSWER: Vector Quantity
States of Matter
Riddle 28: I am anything that has mass and occupies space. I exist in various states: solid, liquid, gas and plasma. Everything physical around you is made of me. Who am I?
ANSWER: Matter
Riddle 29: I am a state of matter with closely packed molecules arranged in a regular pattern. I maintain a fixed shape, mass and volume. Strong intermolecular forces prevent my particles from easily moving past one another. Who am I?
ANSWER: Solid (Solid State)
Riddle 30: I am a state of matter where molecules are close together but not as tightly packed as in a solid. I have a fixed volume but take the shape of my container. I am less compressible than a gas because of my intermolecular forces. Who am I?
ANSWER: Liquid (Liquid State)
Riddle 31: I am a state of matter where molecules are spaced far apart and move freely in all directions. I have neither a fixed shape nor a fixed volume, expanding to fill my container entirely. My weak intermolecular forces allow me to be easily compressed. Who am I?
ANSWER: Gas (Gaseous State)
Riddle 32: I am the fourth state of matter, often forgotten. I am a mixture of positively charged ions and negatively charged electrons. I am formed when a gas becomes so hot that electrons are stripped away from their atoms. Stars, lightning and fluorescent lights are places where I can be found. Who am I?
ANSWER: Plasma
Density
Riddle 33: I am how much substance is packed into a given space. I am defined as the mass per unit volume of a substance at a particular temperature. If I am greater than that of water, an object sinks; if I am less, it floats. Who am I?
ANSWER: Density