# Why won’t anyone answer my questions? I give 10 pts to first answer?

0

A motorboat travels directly east. During its trip, winds blow from directly north, directly south, and southwest. Which of the following statements is true?

All of the winds do work on the boat.

Only the north wind does work on the boat.

Only the south wind does work on the boat.

Only the southwest wind does work on the boat.

• Answer: Only the southwest wind does work on the boat.

Reason: The other forces are perpendicular to the direction of movement of the boat. Therefore work done by those forces = 0.

_______________________________.

• Work is the dot product of force and direction, right? The north and south winds are perpendicular to the motion and therefore do no work on the boat. The southwest wind does work on the boat; in particular, it’s the “west” component of the southwest wind that does work on the boat.

• The north wind does work on the boat

• The work done by the north wind is equal and opposite to the work done by south wind.

So they get cancelled.

So only the southwest wind act on the boat

Since the boat is moving in east the southwest wind deflects its direction slightly from east to north-east.

• All of the winds do work on the boat.

• All of the winds do work on the boat

that my guess

• They would all do work on the boat.

Also Check This  How come the crowd noise is so much louder than the announcers whenever I watch a sporting event on my HDTV?