Can anyone help me with PHYSICS PROBLEM!?

Question

Please help me with my physics hw! Im super lost..Can u also explain how u got the answer as well? Thank you so much! :)

1. A barge is moving due east with a speed of 3.00 m/s (relative to the water) in a river that has a current of 1.50 m/s due south (relative to the shore). On the barge a dog is running at 5.00 m/s at an angle of 25 degrees south of due east (relative to the barge) as shown.

a. What is the magnitude and direction of the barge's velocity relative to someone standing on the shore?

b. What is the magnitude and direction of the dog's velocity relative to someone standing on the shore?

c. What is the magnitude and direction of the dog's velocity relative to someone floating down the river in an inner-tube?

Answer 1

I can't do it here, but draw diagrams for a visual and solve these like simple right triangles, with vector addition as needed.

In each case, let:

A = east vector,

B = south vector,

C = resultant vector,

Θ = angle

a.) magnitude and direction of barge

A = 3.00 m/s

B = 1.50 m/s

C = √(a² + b²)

arctan (Θ) = B/A ESE

b. magnitude and direction of dog

C = given

Θ = given

A = 5.00 cos(Θ)

B = 5.00 sin (Θ)

Do vector addition of A & B to that from part a, and figure the resultant and new Θ.

c. dog's magnitude and direction relative to floater:

A and B are the same as in part a. All the floater sees is the dog's motion relative to the barge.

Wish I could help more, but I've been up for a looooooong time. Here's a good reference to help you:

http://www.glenbrook.k12.il.us/gbssci/ph...

Good luck, and don't panic. I sucked at science and math in H.S. then aced both in college. Of course that was during the Middle Ages :-0) .