Calc

posted by .

At noon, ship A is 40 nautical miles due west of ship B. Ship A is sailing west at 19 knots and ship B is sailing north at 20 knots. How fast (in knots) is the distance between the ships changing at 7 PM?

i really don't have any idea what to do...

  • Calc -

    The relative velocity vector is
    Vab = Va - Vb = -19*t i + 20t j
    where i is a unit vector east and j is a unit vector north.

    The magnitude of that vector is the rate of change of the distance between them, and is
    |Vab| = sqrt[19^2 + 20^2] = 27.59 knots

    That rate is a constant, and does not depend upon time of day nor the initital 40 n.m. separation. You have been given more information than you need.

    The actual separation distance at any time DOES depend upon time and initial separation.

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Calc

    At noon, ship A is 30 nautical miles due west of ship B. Ship A is sailing west at 16 knots and ship B is sailing north at 15 knots. How fast (in knots) is the distance between the ships changing at 7 PM?
  2. Calc

    At noon, ship A is 50 nautical miles due west of ship B. Ship A is sailing west at 20 knots and ship B is sailing north at 20 knots. How fast (in knots) is the distance between the ships changing at 4 PM?
  3. CALCULUS

    At noon, ship A is 40 nautical miles due west of ship B. Ship A is sailing west at 23 knots and ship B is sailing north at 19 knots. How fast (in knots) is the distance between the ships changing at 5 PM?
  4. Calc

    At noon, ship A is 50 nautical miles due west of ship B. Ship A is sailing west at 15 knots and ship B is sailing north at 18 knots. How fast (in knots) is the distance between the ships changing at 6 PM?
  5. calculus

    At noon, ship A is 30 nautical miles due west of ship B. Ship A is sailing west at 25 knots and ship B is sailing north at 25 knots. How fast (in knots) is the distance between the ships changing at 6 PM?
  6. calculus

    At noon, ship A is 10 nautical miles due west of ship B. Ship A is sailing west at 15 knots and ship B is sailing north at 15 knots. How fast (in knots) is the distance between the ships changing at 3 PM?
  7. calculus

    At noon, ship A is 10 nautical miles due west of ship B. Ship A is sailing west at 15 knots and ship B is sailing north at 15 knots. How fast (in knots) is the distance between the ships changing at 3 PM?
  8. calculus

    At noon, ship A is 10 nautical miles due west of ship B. Ship A is sailing west at 15 knots and ship B is sailing north at 15 knots. How fast (in knots) is the distance between the ships changing at 3 PM?
  9. Calculus

    At noon, ship A is 50 nautical miles due west of ship B. Ship A is sailing west at 19 knots and ship B is sailing north at 24 knots. How fast (in knots) is the distance between the ships changing at 3 PM?
  10. calc

    At noon, ship A is 30 nautical miles due west of ship B. Ship A is sailing west at 17 knots and ship B is sailing north at 16 knots. How fast (in knots) is the distance between the ships changing at 6 PM?

More Similar Questions