1. A LEVEL PHYSICS Year 1 Scalars and Vectors C B A A* Know whether a quantity is scalar or a vector (Grade C). Understand the difference between a scalar and vector quantity (Grade B). Be able to add two perpendicular vectors by calculation or scale drawing (Grade A). Be able to resolve a vector into two components at right angles to each other by the use of resolved forces of the use of a closed triangle (Grade A).

3. Stacey is running late for the flight to CERN. She walks briskly to the gate at 2.00 m/s. She then sees a moving walkway moving at 1.50 m/s and decides she will move faster by jumping on and walking at the same speed. What is her total speed? Emily has had enough of Rob’s sunglasses and decides to walk home. She starts to walk at 3.40 m/s, unfortunately in the confusion she jumps on the walkway in the wrong direction. What is her total speed? To start

4. What is the difference between a scalar and a vector? Vectors have both magnitude and direction Scalars have only magnitude Can you think of any examples?

5. Arrange these quantities into scalars or vectors… DistanceSpeedVolume MassMomentumTemperature Electric currentDensityVelocity PressureDisplacementEnergy AccelerationForceweight Remember: Scalar: Quantities that have only magnitude Vectors: Quantities that have both magnitude and direction Scalarvector DistanceDisplacement SpeedVelocity MassWeight PressureForce EnergyMomentum TemperatureAcceleration VolumeElectric current Density

6. Representing vectors Draw diagrams to represent the following scenarios: 1.A force of 6N acting downwards and a force of 7N acting to the right. 2.A boat going across a river at 4 m/s with a current going downstream at 5 m/s. 3.A microlight travelling at 40 m/s east in a cross wind from the south of 10 m/s. Vector quantities have both magnitude and direction. The length of the arrow represents the magnitude of the vector The direction of the arrow represents the direction of the vector The resultant force is represented by an arrow showing the forces combined.

7. Resolving vectors mathematically Finding the resultant Method 1 1.A boat going across a river at 4 m/s with a current going downstream at 5 m/s. 2.A microlight travelling at 40 m/s east in a cross wind from the south of 10 m/s. Draw a scale drawing of the two vectors ‘tip-to-tail’. Measure the length and angle of the resultant vector on the diagram. A B C Distance = A + B Displacement = C

8. Resolving vectors mathematically Finding the resultant a and b are the sizes/magnitu des of vectors a and b.

9. Resolving vectors mathematically Finding the resultant 1.A boat going across a river at 4 m/s with a current going downstream at 5 m/s. 2.A microlight travelling at 40 m/s east in a cross wind from the south of 10 m/s. Determine the magnitude and direction of the resultant. Compare these values to your diagrams.

10. Practice questions In a tug-o-war one team pulls to the left with a force of 600N. The other to the right with a force of 475 N. 1.Draw a vector diagram to show these forces 2.What is the magnitude and direction of the resultant force Two ropes are tied to a large boulder. One rope is pulled with a force of 400N due East. The other rope is pulled with a force of 300N due South. 1.Draw a vector diagram to show these forces 2.What is the magnitude and direction of the resultant force on the boulder?

11. Practice questions A javelin is thrown at 20 m/s at an angle of 45 o to the horizontal. 1.What is the vertical component of this velocity? 2.What is the horizontal component of this velocity? A ball is kicked with a force of 120 N at 25 o to the horizontal. 1.Calculate the horizontal component of the force. 2.Calculate the vertical component of the force.

12. Next Lesson: Resolving vectors into their components Lesson after that: