You’re a tourist in London and want to travel Westminster to Green Park.How do you get there?TFL UPDATE:  Jubilee Line is Down due to engineering works.Using the tube how do you reach Green Park now?
Green Park (G) gvWestminster        (W)Victoria(V)wLet the Jubilee line from Westminster (W) to  Green Park (G) be the vector WG = g.Let the District line from Westminster (W) to Victoria (V) be the vector  WV = w .Let the Victoria line from Victoria (V) to Green Park (G) be the vector VG = v.Westminster to Green park = WG = gand= w+ vWestminster to Green park = WV + VGSo WG = WV + VG 		Then w+ v= g
Triangle Law of Vector  AdditionBy the Triangle Law of Vector Addition: AB + BC = AC   a + b = cWhenc = a + bthe vector c is said to be the RESULTANT of the two vectors a and b. 
A fellow tourist in London asks you how to get from Green Park to South Kensington.How do you get there?TFL UPDATE:  Piccadilly Line is shut due to broken down train.Using the tube how do you reach South Kensington now?
Green Park (G) kgSouth Ken (K)Victoria(V)vLet Green Park (G) to South Ken (K) be the vector GK = k.Let  Green Park (G) to Victoria (V) be the vector  GV = g .Let Victoria (V) to South Ken (K) be the vector VK = v.Green Park to South Kensington = GK = kand= g + v Green Park to South Kensington = GV + VKSo GK =   GV + VK 		Theng+ v = k
WHICH TWO WAYS GET YOU GET FROM BANK TO LIVERPOOL STREET?
Liverpool Street (L) Moorgate (M)mblBank (B)Let Bank (B) to Liverpool Street (L) be the vector BL = lLet Bank (B) to  Moorgate (M) be the vector  BM = bLet  Moorgate (M) to Liverpool Street (L) be the vector MV = mSo Bank to Liverpool Street = BL = land= b+ mBank to Liverpool Street = BM + MLSo BL =   BM + ML 		Then b+ m= l
AD = AC + CDAD = a + b + cAC = AB + BCAC = a + b
i) AB = AO + OB    AB = -a + b = b - aii) AP = ½ AB       AP = ½ ( b – a)      ii) OP = ½ AB + OA      OP = ½ ( b – a) + a
358Suppose a=b=and–231baa + b  =a + bThe Triangle Law of Vector AdditionAdding two vectors is equivalent to applying one vector followed by the other. For example,Find a + bWe can represent this addition in the following diagram:
caIn general, if a=b=anddba + ca + b=b + dAdding VectorsWhen two or more vectors are added together the result is called the resultant vector.We can add two column vectors by adding the horizontal components together and adding the vertical components together.
Adding Vectors
–24Suppose andb=a=34–2644 – –2–==3144 – 3Subtracting VectorsWe can subtract two column vectors by subtracting the horizontal components and subtracting the vertical components. For example,Find a – ba – b =
–24andb=a=34b–b–baaa – b6a – b  =1Subtracting VectorsTo show this subtraction in a diagram, we can think of a – b as a + (–b).
Adding and Subtracting Vectors

Triangle law of vector addition

  • 1.
    You’re a touristin London and want to travel Westminster to Green Park.How do you get there?TFL UPDATE: Jubilee Line is Down due to engineering works.Using the tube how do you reach Green Park now?
  • 2.
    Green Park (G)gvWestminster (W)Victoria(V)wLet the Jubilee line from Westminster (W) to Green Park (G) be the vector WG = g.Let the District line from Westminster (W) to Victoria (V) be the vector WV = w .Let the Victoria line from Victoria (V) to Green Park (G) be the vector VG = v.Westminster to Green park = WG = gand= w+ vWestminster to Green park = WV + VGSo WG = WV + VG Then w+ v= g
  • 3.
    Triangle Law ofVector AdditionBy the Triangle Law of Vector Addition: AB + BC = AC  a + b = cWhenc = a + bthe vector c is said to be the RESULTANT of the two vectors a and b. 
  • 4.
    A fellow touristin London asks you how to get from Green Park to South Kensington.How do you get there?TFL UPDATE: Piccadilly Line is shut due to broken down train.Using the tube how do you reach South Kensington now?
  • 5.
    Green Park (G)kgSouth Ken (K)Victoria(V)vLet Green Park (G) to South Ken (K) be the vector GK = k.Let Green Park (G) to Victoria (V) be the vector GV = g .Let Victoria (V) to South Ken (K) be the vector VK = v.Green Park to South Kensington = GK = kand= g + v Green Park to South Kensington = GV + VKSo GK = GV + VK Theng+ v = k
  • 6.
    WHICH TWO WAYSGET YOU GET FROM BANK TO LIVERPOOL STREET?
  • 7.
    Liverpool Street (L)Moorgate (M)mblBank (B)Let Bank (B) to Liverpool Street (L) be the vector BL = lLet Bank (B) to Moorgate (M) be the vector BM = bLet Moorgate (M) to Liverpool Street (L) be the vector MV = mSo Bank to Liverpool Street = BL = land= b+ mBank to Liverpool Street = BM + MLSo BL = BM + ML Then b+ m= l
  • 8.
    AD = AC+ CDAD = a + b + cAC = AB + BCAC = a + b
  • 9.
    i) AB =AO + OB AB = -a + b = b - aii) AP = ½ AB AP = ½ ( b – a) ii) OP = ½ AB + OA OP = ½ ( b – a) + a
  • 10.
    358Suppose a=b=and–231baa +b =a + bThe Triangle Law of Vector AdditionAdding two vectors is equivalent to applying one vector followed by the other. For example,Find a + bWe can represent this addition in the following diagram:
  • 11.
    caIn general, ifa=b=anddba + ca + b=b + dAdding VectorsWhen two or more vectors are added together the result is called the resultant vector.We can add two column vectors by adding the horizontal components together and adding the vertical components together.
  • 12.
  • 13.
    –24Suppose andb=a=34–2644 ––2–==3144 – 3Subtracting VectorsWe can subtract two column vectors by subtracting the horizontal components and subtracting the vertical components. For example,Find a – ba – b =
  • 14.
    –24andb=a=34b–b–baaa – b6a– b =1Subtracting VectorsTo show this subtraction in a diagram, we can think of a – b as a + (–b).
  • 15.