A river with straight and parallel banks has a width of 0.76 km. The stream flow

Question

A river with straight and parallel banks has a width of 0.76 km. The stream flows down to 4km / h and is parallel to the margins. The boatman driving a barge that can reach a maximum speed of 8 km / h in still waters wishes to go from A to B, where AB is perpendicular to the shore. The boatman must. a) Direct the boat directly across the river, perpendicular to the shore following AB. b) set a course 45 ° directed upstream from the direction AB. c) heading 30 ° directed upstream with respect to direction AB. d) to resign since it is impossible to go from A to B with a ship of these characteristics.

Explanation / Answer

here,

as the river speed is 4 km/h to the right

so to reach the point B from A

the horizontal component of velocity of boatman relative to ground must be zero

so, the horizontal component of velocity of boatman reltaive to river must be - 4 km/h

the angle , theta = arcsin(4/8)

theta = 30 degree

sp the boatman must c) heading 30 ° directed upstream with respect to direction AB

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.