lals asked in Science & MathematicsPhysics · 1 month ago

Physics help with vector q plssss?

Where bearings are given, they are in degrees East of North (so North is 000∘, East is 090∘, South is 180∘ and West 270∘). For the purposes of this exercise, assume the Earth is flat.

a) In which direction would I have to travel in order to travel North (relative to a stationary observer) if I am swimming in a river with a current running 0.40ms−1 to the East, and I can swim at 1.5ms−1 relative to the water? Give your answer as a bearing (degrees clockwise from North) to 3 significant figures.

How did you get the answer- would very much be appriciated :) 

1 Answer

  • 1 month ago
    Favorite Answer

    The westward component of the swimmer's speed must be 0.40 m/s, to cancel exactly the eastward flow of the river. So if the swimmer is going 1.5 m/s, we can say cos(theta) = 4/15, where theta is the angle north of WEST. Using a calculator, you get theta = 74.534. However, they want the answer given as a bearing clockwise from north, so you get 270 + 74.534 = 344.5, but round off to 345 degrees.

    • Commenter avatarLogin to reply the answers
Still have questions? Get your answers by asking now.