Speed & Velocity
Is speed a vector quantity or scalar quantity? Why?
scalar; only has magnitude
How is acceleration calculated?
acceleration = change in velocity/time
What is the equation for calculating speed?
speed = distance/time
What is the equation for acceleration?
change in velocity/time
What is the equation for calculating velocity?
velocity = displacement/time
Is acceleration a scalar or a vector quantity? Why?
vector; has magnitude and direction
An object travels 4 m in 2 s. What's the speed?
2 m/s
What are the metric units for acceleration?
m/s2
An object travels 15 km south in 0.5 hour. What's the velocity?
30 km/h to the south
What can a negative acceleration mean? Give two explanations.
slowing down
accelerating in reverse
Is velocity a vector quantity or scalar quantity? Why?
vector; has magnitude and direction
If an object has constant velocity, what van be said about its acceleration?
a = 0 m/s2
What does a negative velocity mean?
traveling backward/down/west/left
An object's velocity increase from 0 m/s to 20 m/s in 2 seconds. What's the acceleration?
(20 m/s - 0 m/s)/2 s = 10 m/s2
An object travels at 10 m/s for 5 seconds. How far did it travel?
s = d/t
t*s = d
(5 s)(10 m/s) = 50 m
A car traveling at 45 m/s increases its velocity to 80 m/s in 5 s. What is its acceleration?
7 m/s2
An object travels backward at a velocity of 20 m/s for 4 s, what is the displacement?
80 m backward
vi = 40 m/s
vf = 20 m/s
t = 5 s
-4 m/s2
v = 10 m/s
d = 70 m
t = ?
7 s
A car speeds up from 0 to 60 km/h in 60 minutes. What was its acceleration in?
60 km/h