This lesson explains the command words used in IGCSE Physics exam questions. Each word tells you what type of answer the examiner expects.
State
Give a fact or value without explanation. Keep it short. Example: “State the SI unit of force.” Answer: “Newton (N).”
Define
Give a precise physics definition. Use the exact wording from the syllabus. Example: “Define acceleration.” Answer: “The change in velocity per unit time.”
Describe
Say what happens, step by step. Do not give reasons. Example: “Describe what happens to the temperature of ice as it is heated.” Answer: “The temperature increases from below 0 degrees C to 0 degrees C, remains constant at 0 degrees C while the ice melts, then increases again.”
Explain
Give the physics reason for an observation. Include cause and effect. Example: “Explain why metals are good conductors.” Answer: “Metals contain free electrons that can move through the structure, transferring kinetic energy from one part to another.”
Calculate
Use numbers and an equation to find a value. Show your working. State the unit. Example: “Calculate the resistance.” Show: V = IR, R = V/I, R = 12/0.5 = 24 ohms.
Suggest
Give a plausible answer that may not be directly in the syllabus. Use your physics knowledge to reason. Example: “Suggest why the student’s result is different from the accepted value.” Answer: “Thermal energy was lost to the surroundings, so the calculated specific heat capacity is higher than the true value.”
Compare
State the similarities and/or differences between two things. Use linking phrases like “whereas,” “both,” “unlike.” Example: “Compare alpha and beta radiation.” Answer: “Both are emitted from the nucleus. Alpha has a charge of +2 and is stopped by paper, whereas beta has a charge of -1 and is stopped by thin aluminium.”
Evaluate
Weigh up evidence or arguments and reach a justified conclusion. Example: “Evaluate whether wind power is suitable for the country.” Answer: Give points for and against, then state which outweighs the other and why.
Determine
Find a value from a graph, diagram or data, often without a formula. Example: “Determine the gradient of the graph.” Read two points on the line, calculate rise/run.
Sketch
Draw a rough but recognisable diagram or graph. Key features must be correct (shape, labels, proportions), but exact values are not needed.
Need a Plan Based on Actual Work?
A private taught trial can help distinguish whether the repeated difficulty is mainly Physics knowledge, Mathematics, practical reasoning or exam technique before regular lessons are discussed.