Physical Sciences

1. MOTION

4. s = _d_
t
d = s t t = _d_
s
d
s tX

6. 1. If a school bus moves 1600 meters at an average
speed of 15.5 m/s, how long did the journey take?
2. An electron in orbit around an atom moves at a speed
of 2500 km/s. How far would it travel (in a straight
line) if it moved at this speed for 1 minute?

7. Average Speed = total distance traveled
total time
S = _dt_
tt
This is useful when you are trying to
measure speed, and the object moved at
varying speeds throughout the trip. For
instance, if you drove from here to
Manila, you might AVERAGE 70 mph, even
though you stopped at lights, or slowed
down or even reached 80 at some points
in your trip.

8. Joe drives 120 miles at 60 miles per hour, and then he
drives the next 120 miles at 40 miles per hour. What is
his average speed for the entire trip in miles per hour?
A) 42
B) 48
C) 50
D) 54
E) 56

9. What is Velocity?
Velocity is a measure of the speed of an
object AND the direction it is moving in
space.
On the escalator, passengers are moving
at the same constant speed, but they are
moving in different directions.
Velocity can change even if speed is
remaining constant (you just change
direction)

10. Velocity = distance V = _d_
time t
time

13. 1. A cyclist increases her speed from 5 m/s to 19 m/s in 7
seconds, what is her acceleration?
2. An oil tanker can decelerate at a maximum rate of 0.04
m/s2. How long will the tanker take to come to a complete
stop if initially travelling at a speed of 12 m/s?
3. A football moving forwards at a speed of 12.4 m/s is kicked
forwards so that its speed increases. The acceleration of
the ball is 48.0 m/s2, which lasts for 0.45 seconds. What’s
the final speed of the ball after this acceleration?