Vocabulary Quiz- (1D Motion) Wednesday

Vector vs Scalar

Most of the quantities used to describe motion can be categorized as either vectors or scalars.

A vector is described by magnitude (size) and direction

Example.. Where is Big Spring? 40 mi, East

A scalar is described by magnitude (size) only

Example…How fast is the speed limit? 70 mph

Review

A quantity that is ignorant of direction is referred to as a _________________.

a. scalar quantity b. vector quantity

3. A quantity that is conscious of direction is referred to as a _________________.

a. scalar quantity b. vector quantity

a. scalar quantity

B. vector quantity

In which movie have you heard the word Vector?

http://www.youtube.com/watch?v=GKQdkS0qG3g

Distance vs- Displacement

I. Distance and Displacement 1) Distance and displacement are similar but

different a) Distance is a scalar quantity which

refers to “the amount of ground an object has covered" during its motion.

b) Displacement is a vector quantity which refers to “the overall change in position of the object from start to finish”. You can think of it as the distance “the shortest distance that the crow flies”.

What is the car’s distance, what is the car’s displacement?

The car covered a distance of 25 km and a displacement of 10 km, East

What distance did Tim travel? What was Tim’s displacment?

Tim covered a distance of (3m + 4m) = 5 m and a displacement of 5 m, NE

What is the distance the physics student travelled? What is their

displacement?

Example- A physics student walks 4 meters East, 2 meters South, 4 meters West, and finally 2 meters North.

The student covered a distance of 12 m (4m + 2m + 4m +2 m) = 12 meters

and has a displacement of O m

Distance vs- Displacement

A football coach paces back and forth along the sidelines- the coach moves from position A to B to C to D. What is his distance covered and displacement?

The coach covers a distance of (35 yds + 20 yds + 40 yds) = 95 yards

and has a displacement of 55 yards, left.

Review

What is the distance and the displacement of the race car drivers in the Indy 500?

The displacement of the cars is somewhere near 0 miles since they virtually finish where they started. Yet the successful cars have covered a distance of 500 miles.

Review

Scalar

Scalar

Vector

Is speed a vector or scalar?

Is distance a vector or scalar?

Is displacement a vector or scalar?