Scalars/Vectors
What is a scalar quantity?
A quantity with only a magnitude (no direction)
What is the difference between distance and displacement?
Displacement is a straight line from where you started to where you ended. Distance is total distance.
It takes a car 20 seconds to travel 1000 meters. How fast, on average, was the car moving?
Speed = 50 m/s
You walk 67 meters east in 6.7 seconds. What is your velocity?
10 m/s East
What is the displacement in section A
60 meters East
What is a vector quantity?
A quantity with both a magnitude and a direction.
Whats wrong with my answer to this question?
You walk 30 meters North, then walk 40 meters South,
Distance = 70 meters
Displacement = 10 meters North
Displacement = 10 meters South or -10 meters
You run 50 meters in 6 seconds. What is your speed?
speed = 8.33 m/s
If a plane travels 1000 km in 2hrs from Indianapolis to Orlando Floride (South), what is its velocity?
500 km/hr south
In section B, the object is motionless. For how long?
5 seconds
45,000 km. Is this a scaler quantity or a vector quantity?
Scalar, because the quantity only has a magnitude (an amount), and no direction.
The starting point of a question is labeled with what symbol?
A) df B) Rf C) di D) Home
C) di stands for initial position. Reference point can be the starting point but is not always.
You run 100 meters in 24 seconds. What is your speed?
speed = 4.17 m/s
You run 1300 meters north in 233 seconds, then turn around and run 350 meters south in 1 minute.
What are both of your individual velocities?
Velocity 1 = 5.58 m/s North
Velocity 2 = 5.83 m/s South or -5.83 m/s
What is the displacement in section D?
40 meters East
Is Speed a vector or scalar quantity?
Scalar
Juana walks 300 meters West, then 200 meters East. What is her total distance traveled? Displacement? Draw a picture.
Distance = 500 m Displacement = 100 m West
How long would it take for a dog that runs at 4 m/s to travel 28 meters?
Time = Distance/Speed Time = 28 meters/4m/s Time = 7 seconds
You run 1300 meters north in 233 seconds, then turn around and run 350 meters south in 1 minute.
What is your average velocity over this whole scenario?
displacement = 1300 - 350 = 950 meters North
Time = 233 + 60 = 293 seconds
Velocity = 3.24 m/s North
What is the displacement in section C?
100 meters West or -100 meters
How do combine vectors that are going to two different directions ? ex: 4m north and 5m east and find displacement?
What is the Pythagorean theorem ( formula )
a2 + b2 = c2
Luis walk 20 meters south, 10 meters East, 30 meters North, then 10 meters West. What is the distance traveled? Displacement? DRAW A PICTURE.
Distance = 70 m Displacement = 10 m North
if you drive at 100 km/h for a minute and 15 seconds, how far did you drive?
1 minute and 15 s = 75 seconds = 1 .25 mins
1.25 mins = 0.020833333 hours.
distance = speed (km/h) x time (h)
distance = 2.08 km
2 planes leave the same airport at the same time going opposite directions. Plane A goes East at 220 km/h. Plane B goes West at 245 km/h. How far apart are the 75 mins later?
time = 75 mins = 1.25 hours.
Plane A displacement = 220 km/h x 1.25 = 275 km East
Plane B displacement = 245 x 1.25 = 306.25 km W
Distance apart = 275 + 306.25 = 581.25 km apart
What is the velocity in section C?
displacement = -100m
time = from 15 to 40 = 25 seconds.
velocity = -4 m/s or 4 m/s West