1.3) \ \

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Speed of Vehicle V  vv = 125 km/h in north-east direction. \ \

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Speed of Vehicle W  vw = 125 km/h in east direction. \ \

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Consider that two vehicles are starts from same point. \ \

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\"\" \ \

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By using vector analysis \ \

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OA = 125 km/h \ \

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OB = 125 km/h \ \

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OA = BC \ \

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OB = AC \ \

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AB = CD \ \

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OD = OB+BD \ \

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OC = Relative velocity magnitude \ \

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∠OCD = Relative velocity angle \ \

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From above figure \ \

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Angle ∠NOE = 90° \ \

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Angle ∠AOB is half in NOE \ \

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Angle ∠AOB = ∠CBD = θ = 45° \ \

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From CBD right angled triangle \ \

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sinθ = BC/CD \ \

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BC = CD sin 45° \ \

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BC = 125 sin 45° \ \

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BC = 88.388 km/h \ \

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From CBD right angled triangle \ \

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cosθ = BD/CB \ \

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BD = CB cos 45° \ \

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BD = 125 cos 45° \ \

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BD = 88.388 km/h \ \

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OD = OB+BD = 125+88.388 = 213.388 km/h \ \

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From OAB right angled triangle \ \

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sinθ = AB/OA \ \

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AB = OA sin45 \ \

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AB = 125 sin45 \ \

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AB = 88.388 km/h \ \

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AB = CD = 88.388 km/h \ \

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From OCD right angled triangle \ \

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OC² = OD² + CD² \ \

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OC² = 213.388² + 88.388² \ \

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OC = 230.969 km/h \ \

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∠OCD = tan-1(88.388/213.388) \ \

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∠OCD = 22.3° \ \

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Solution : \ \

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Magnitude of the velocity of vehicle W relative to the velocity of vehicle V is 230.969 km/h \ \

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Direction of the velocity of vehicle W relative to the velocity of vehicle V is 22.3° upside inclined to east \ \