Magnitude and direction of <0, -7>

Step by step

The question

Question: find the magnitude and the direction of v = ⟨0, −7⟩.

1 Draw the arrow

Draw the grid.

The arrow starts at the origin.

It goes down 7.

2 Find the length

The arrow goes straight down.

So its length is just 7.

3 Read the angle

The arrow points straight down: three quarter turns.

So θ = 270°.

So the magnitude is 7 and the direction is 270°.

4 Check

Let's check on the grid: the green arc turns to the arrow.

That is 270°.

Right!

Let's look back.

First: draw the arrow.

Then: find the length.

Then: read the angle.

Last: check.