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Rates of change and differential equations — Question 17

QCAA 2020, Paper 2 · 7 marks

Q17 · 2020 · Technology-activeComplex familiar7 marks

QUESTION 17 (7 marks)

An object is released from rest at a height of 100 m above the ground. The motion of the vertical descent of the object is modelled by vdvdx=9.8−0.004v2,v≥0,v\frac{dv}{dx}=9.8-0.004v^2,\qquad v\ge0, where vv is the velocity (m s−1^{-1}) and xx is the displacement from the ground (m). Determine the velocity of the object when it strikes the ground.
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