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Time intervals x = 4cos( π t) Find the time interval between the 1st and 2nd time the particle is at x = 3. x = 3 so 3 = 4cos π t = cos π t so π t = 0.7227 or 2π – 0.7227 So t = 0.153 or 1.180 s so time interval is 1.03 s.
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Time intervals x = 4cos(π t) Find the time interval between the 1st and 2nd time the particle is at x = 3. x = 3 so 3 = 4cos π t = cos π t so π t = 0.7227 or 2π – 0.7227 So t = 0.153 or 1.180 s so time interval is 1.03 s
x = 4cos π t Find the time interval between the 2nd and 3rd time the particle has speed 15m/s. Differentiating, v = –6π sin( π t) The graph shows when the speed is 15m/s. ±15 = –6π sin( π t) π t = 0.9203 or π – 0.9203 or π + 0.9203 So t = 0.195, 0.471, 0.862 s The time interval between the 2nd and 3rd time the particle has speed 15m/s is 0.391s.