1.2 | Basics of Kinematics

A quantity that has only a size or amount is called a

• scalar

• vector

• magnitude

• direction

A quantity that has both an amount and a direction is called a

• vector

• scalar

• magnitude

• mantissa

We call how large or small a measurement is its

• magnitude

• mantissa

• displacement

• azimuth

You just ran 3 km east and 4 km south. Your Fitbit says you've traveled 7 km. The name for that measurement is your

• distance traveled

• displacement

• speed

• velocity

You just ran 3 km east and 4 km south. Your smartphone says you're 5 km southeast of your starting point. The name for that measurement is your

• distance traveled

• displacement

• speed

• velocity

The difference between speed and velocity is that

• speed has a direction but velocity does not.

• velocity has a direction but speed does not.

• velocity is a scalar but speed is a vector.

• there is none -- they're the same thing.

Mr. B walks 30 m east towards his car.

He thinks he forgot his keys, so he turns around and walks 10 m west.

He notices his keys are in his hands, so he walks the other 40 m east to his car.

This takes 30 seconds.

What distance did he travel?

• 10 m

• 40 m

• 60 m

• 80 m

Mr. B walks 30 m east towards his car.

He thinks he forgot his keys, so he turns around and walks 10 m west.

He notices his keys are in his hands, so he walks the other 40 m east to his car.

This takes 30 seconds.

What is the magnitude of his displacement?

• 10 m

• 40 m

• 60 m

• 80 m

Mr. B walks 30 m east towards his car.

He thinks he forgot his keys, so he turns around and walks 10 m west.

He notices his keys are in his hands, so he walks the other 40 m east to his car.

This takes 30 seconds.

What is the direction of his displacement?

• East

• West

• South

• Displacement doesn't have a direction, speed does.

Mr. B walks 30 m east towards his car.

He thinks he forgot his keys, so he turns around and walks 10 m west.

He notices his keys are in his hands, so he walks the other 40 m east to his car.

This takes 30 seconds.

What is his average speed?

• 1.33 m/s

• 2.67 m/s

• 2.00 m/s

• 0 m/s: He's moving back and forth so it cancels out.