Robin rides a personal watercraft 75° west of south at 70 miles/hour. the water current is moving 6 miles/hour at an angle of 75
2 answers:
Answer:
Actual speed = 73.18 m/s
Step-by-step explanation:
Let positive x axis represent east and positive y axis represent north.
Robin rides a personal watercraft 75° west of south at 70 miles/hour.
Velocity of personal watercraft = 70 miles/hour at 75° west of south
= 70 miles/hour at 15° south of west
= -70 cos 15 i + -70 sin 15 j
= -67.61 i - 18.12 j
The water current is moving 6 miles/hour at an angle of 75° south of west.
Velocity of water current = 6 miles/hour at 75° south of west
= 6 miles/hour at 75° south of west
= -6 cos 75 i + -6 sin 75 j
= -1.55 i - 5.80 j
Total velocity = -67.61 i - 18.12 j -1.55 i - 5.80 j = -69.16 i - 23.92 j
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