FORCES AND SHAPE
4 marks · HardA student claims that temperature is a vector quantity. She says this because temperature can rise or fall, and you can measure how quickly it changes.
Explain, with reasons, whether temperature is a vector or scalar quantity.
Give two reasons why force is a vector quantity and not a scalar quantity.
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(a) Temperature is a scalar quantity because it only has size (magnitude) and no associated direction. Vectors must have both size and direction; just increasing or decreasing is not a direction. · must show States temperature is a scalar, Explains no associated direction
(b) Force is a vector because: 1. It has a size and a direction; its effect depends both on how big the force is and which direction it acts. 2. Combining forces requires considering their directions, not just adding sizes (vector addition). · must show States force has direction as well as size, States the effect/addition depends on direction
Common mistakes: Assuming temperature has direction because it increases or decreases; Not specifying direction is essential for vectors
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Marking points
B1 (a) · 1 mark · Correctly identifies temperature as a scalar
B2 (a) · 1 mark · Explains temperature has no direction associated
B3 (b) · 1 mark · States force has both size and direction (or equivalent)
B4 (b) · 1 mark · Gives a valid second point (effect depends on direction or combining forces requires vector addition)
Worked solution
a) Temperature is a scalar because it only has a magnitude (size); it does not act in any direction in space. Vectors require both magnitude and direction.
b) Force is a vector quantity because (1) it has both a size and a direction, and (2) the result when forces are combined depends on their directions (vector addition), not just their sizes.