Vector and scalar quantities

Question 1

Define scalar and vector

Answer 1

• A vector is a quantity with both direction and magnitude
• A scalar is a quantity with just magnitude

Question 2

Examples of scalars

Answer 2

• Distance
• Speed
• Time
• Density
• Pressure
• Temperature
• Mass
• Work or energy

Question 3

Examples of vectors

Answer 3

• Displacement
• Velocity
• Acceleration
• Force
• Momentum

Question 4

Appreciate the concept of vector displacement and contrast it with distance

Answer 4

• Displacement is a vector quantity, meaning it has both direction and magnitude, when distance has only magnitude, which focuses only on length travelled (without consideration of direction)
• Distance is the length of the path taken whereas displacement is the distance from where you started and where you ended up - the straight line/shortest possible length (where the crow flies)
• Diplacement and distance are only equal when the motion occurs in a straight line or along a single direction

Question 5

Define velocity in terms of displacement

Answer 5

• Velocity is the rate of change of displacement

Question 6

Define speed in terms of velocity

Answer 6

• Speed is the scalar component of velocity