One Dimensional Motion Unit Assessment Quizzes

north is the direction the 15 m is pointing

The unit defines what the 15 is.  15 what?

meters

Magnitude is the number and unit: 15 meters

without any direction

What is your displacement after going 10 meters east followed by 20 meters west in 10 seconds?

Displacement is vector and a measure of how far you are from start to finish.  Take into account the direction.

10 m east becomes (+10)

20 m west becomes (-20)

add them together including the sign ((+10) + (-20))

(-10 meters) or 10 meters west

• What is your velocity after going 10 meters east followed by 20 meters west in 10 seconds?
• Velocity is a vector so direction matters so displacement divided by time.  Make the directions into signs.
• 10 m east is  +10
• 20 m west is -20
• now calculate displacement and divide that by time ((+10)+(-20))/10
• -10/10 = -1 m/s
• turn the negative back into a direction 1 m/s west

What is your speed after going 10 meters east followed by 20 meters west in 10 seconds?

speed is a scalar so disregard the direction.

v = x/t

(10 meters + 20 meters) / (10 seconds)

15 m/s is a magnitude only but includes a distance over time so is the scalar speed.

15 m is a magnitude and east is a direction.  This is the vector displacement having both magnitude and direction from the origin to the end.

Displacement  is a vector that includes direction. Make the direction a sign (east positive and west negative) before you add (10 + (-3)) =  -7 meters which becomes 7 meters west

Distance is a scalar that has no direction. You do nothing with the direction and just add all the individual magnitudes up (10 + 3) here.

You can't put a direction on the final answer since it is a measure of how far you went totally and not a direction.

You should not put a direction on the final answer either since this is not a measure of where you are located but just how far you went in any direction.