# Question 4cf43

Jul 11, 2017

We're asked to find the total distance an object travels given the time and the components of its (constant) velocity.

To do this, we can use the time and each velocity component to find the components of its position, using the simple velocity equation

overbrace("velocity")^"(constant)" = "displacement"/"time"

We can split this into $x$- and $y$-components, taking east to be the positive $x$-direction, and north to be the positive $y$-direction:

${v}_{x} = \frac{\Delta x}{\Delta t}$ Solving for position: $\Delta x = {v}_{x} \left(\Delta t\right)$

${v}_{y} = \frac{\Delta y}{\Delta t}$ Solving for position: $\Delta y = {v}_{y} \left(\Delta t\right)$

We know:

• ${v}_{x} = - 40$ $\text{m/s}$ (west is negative direction)

• ${v}_{y} = - 70$ $\text{m/s}$ (south is negative direction)

• $\Delta t = 20$ $\text{s}$

Plugging in known values:

Deltax = (-40"m"/(cancel("s")))(20cancel("s")) = color(red)(-800 color(red)("m"

Deltay = (-70"m"/(cancel("s")))(20cancel("s")) = color(green)(-1400 color(green)("m"

The total distance traveled can be found using the distance formula:

r = sqrt((Deltax)^2 + (Deltay)^2) = sqrt((color(red)(-800)color(white)(l)color(red)("m"))^2 + (color(green)(-1400)color(white)(l)color(green)("m"))^2

= color(blue)(1612 color(blue)("m"

Which if you wish to round to only $2$ significant figures, is

color(blue)(1600 color(blue)("m"#