Motion

Phet Vector Activity

Open up the Phet Interactive called Vector Addition (https://phet.colorado.edu/en/simulation/legacy/vector-addition) Embedded Below

Look at the 2 diagrams below to familiarise yourself with the layout. Note that the scale is such that each small grid square represents a distance of 1 metre (each large square = 5 metres)

Activity 1

Note: Make sure the ‘Show Sum’ is deselected

Imagine you walked 30m east and then 40m north

(a) Represent this journey by using 2 vectors from the ‘vector grab pile’ and placing them head to tail.

(b) What is the distance you have walked

(c) Calculate the final position vector by using Trigonometry and Pythagoras. Remember that your position vector must have a magnitude (in metres) and a direction (in degrees). Make sure that your direction is a TRUE bearing (measured clockwise from North).

(d) Verify your result by now selecting ‘show sum’ (note that the angle displayed will be measured anticlockwise from the x axis. You will need to convert this to a TRUE bearing manually)

Activity 2

Note: Make sure the ‘Show Sum’ is deselected

Clear the previous activity

PART A

Imagine you walked the following directions 50m east then 70m north then 20m west and finally 15 metres south

(a) Represent this journey by using 4 vectors from the ‘vector grab pile’ and placing them head to tail.

(b) What is the distance you have walked

(c) Calculate the final position vector by using Trigonometry and Pythagoras.

(d) Verify your result by now selecting ‘show sum’

PART B

Imagine you walked the following directions 30m north then 70m east then 35m north then 20 metres west then 10m south then 20m west

(a) Represent this journey by using 6 vectors from the ‘vector grab pile’ and placing them head to tail.

(b) What is the distance you have walked

(c) Calculate the final position vector by using Trigonometry and Pythagoras.

(d) Verify your result by now selecting ‘show sum’

(e) How does it compare with the result of part A