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Vectors in two and three dimensions — Question 192

Original QCE Vault practice · 5 marks

Q192 · Practice questionTechnology-freeComplex familiar5 marks

QUESTION 192 (5 marks)

A river is 100 m wide, measured due north. Its current is 3i3\mathbf i m/s east. A boat has speed 5 m/s relative to the water. Let j\mathbf j point north. Ignore acceleration and current changes.
Plan view of a river with two horizontal banks, a northward width dimension of 100 metres and an eastward current arrow of 3 metres per second.
a)
If the boat points north, determine crossing time and eastward drift.
[2 marks]
b)
Determine water-relative velocity for arrival directly opposite, and crossing time.
[3 marks]
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