Vector A has magnitude of 8 units and makes an angle of 45⁰ with the positive x-axis.vector B also has the same magnitude of 8 units and directed along the negative x-axis. find the magnitude and direction of A+B and the magnitude and direction of A-B ?
Apr 09, 2023To find the magnitude and direction of A+B, we can use the following formula: A + B = √(A² + B² + 2ABcosθ) where A = 8 units, B = -8 units (since it is directed along the negative x-axis), θ = 45⁰ (since A makes an angle of 45⁰ with the positive x-axis). Substituting these values, we get: A + B = √(8² + (-8)² + 2(8)(-8)cos45⁰) A + B = √(64 + 64 - 128/√2) A + B = √(128 - 64√2) ≈ 1.14 units To find the direction of A+B, we can use the following formula: tanθ = (Sinθ)/Cosθ where θ = angle between A+B and the positive x-axis. Substituting the values, we get: tanθ = (8Sin45⁰)/(-8 + 8Cos45⁰) tanθ = 1 θ = tan⁻¹(1) = 45⁰ Therefore, the magnitude of A+B is approximately 1.14 units and its direction makes an angle of 45⁰ with the positive x-axis. To find the magnitude and direction of A-B, we can use the same formula as above: A - B = √(A² + B² - 2ABcosθ) Substituting the values, we get: A - B = √(8² + (-8)² - 2(8)(-8)cos45⁰) A - B = √(128 + 64√2) ≈ 11.31 units To find the direction of A-B, we can use the same formula as above: tanθ = (Sinθ)/Cosθ where θ = angle between A-B and the positive x-axis. Substituting the values, we get: tanθ = (8Sin45⁰)/(-8 - 8Cos45⁰) tanθ = -1 θ = tan⁻¹(-1) = -45⁰ Therefore, the magnitude of A-B is approximately 11.31 units and its direction makes an angle of -45⁰ with the positive x-axis.
Apr 10, 2023