Download Acceleration - Spring Branch ISD

Name: _______________________________________
Period: _____
Force & Motion Study Guide

Know your vocabulary & how to use it in context
 Formulas
Bring a calculator!!!!
 Friction
1.
2.
The three types of friction are:
o
Sliding
o
Rolling
o
Fluid (air or liquid)
o
Static
Why is friction important?
Friction is important because it basically allows us to do everyday things: driving a car, picking up objects etc.
Without it everything would just slip and slide, with nothing to grip onto.
 Balanced & Unbalanced Forces
5N
3.
What is the net force?
4.
Is there motion or no motion?
Motion
5.
Is the force balanced or unbalanced?
unbalanced
6.
What is the net force?
17 N right
7.
Is there motion or no motion?
motion
8.
Is the net force balanced or unbalanced?
unbalanced
9.
What is the net force?
0N
10. Is there motion or no motion?
17 N
7 N left
5N
3N
7N
7N
No motion
11. Is the net force balanced or unbalanced? Balanced
25N
25N
 Speed
12. Alex rode his bicycle 60 kilometers in 4 hours. How fast was he going?
D = 60 km
S=
𝑫
𝑻
=
𝟔𝟎 𝒌𝒎
𝟒𝒉
=
15 km/h
T = 4 hr
13. Matt says he is faster than Alex. He rode 93 kilometers in 6 hours. What is Matt’s speed, and who is faster?
D = 93 km
S=
𝑫
𝑻
=
𝟗𝟑 𝒌𝒎
𝟔𝒉
=
15.5 km/h
Matt is faster.
T = 6 hr
14. What is the average speed of a car that travels 90 km in 2 hours, 50 km in 1.5 hour, and 200 km in 3 hours?
D = 90 + 50 + 200km
S=
𝑫
𝑻
=
𝟑𝟒𝟎 𝒌𝒎
𝟔.𝟓 𝒉
=
52.31 km/h
T = 2 + 1.5 + 3 hrs
15. What is the difference between speed and velocity?
The difference between speed & velocity is that velocity is speed with a direction.
 Relationships on a graph
16.
How do you find speed from a graph? Divide distance over time; S =
a.
𝑫𝒇 − 𝑫𝒊
𝑻𝒇 − 𝑻𝒊
What is your x-axis & y-axis?

X-axis time

Y-axis distance
17. Calculate each segment’s speed for the
a. A-B
10 m/s
b. B-C
0 m/s
c. C-D
20 m/s
d. D-E
0 m/s
e. E-F
-10 m/s
f. F-G
0 m/s
g. G-H
10 m/s
graph
h. Which point on the graph shows the
fastest speed? C-D (20 m/s)
 Acceleration
18. Acceleration of an object will occur when the object speeds up, slows down, and changes direction
19.
What is the acceleration of a skateboard if it took 8 seconds for the speed to increase from 10 m/s to 14 m/s?
𝑽𝒇 − 𝑽𝒊
𝒕𝒊𝒎𝒆
=
𝟏𝟒 𝒎/𝒔− 𝟏𝟎 𝒎/𝒔
𝟖𝒔
=
𝟒 𝒎/𝒔
𝟖𝒔
=
0.5 m/s2
20.
If you roll a marble down the sidewalk, and its speed increases from 2.5 m/s to 6 m/s in 10 seconds, what is the
acceleration of the marble?
𝑽𝒇 − 𝑽𝒊
𝒕𝒊𝒎𝒆
21.
=
𝟔𝒎/𝒔− 𝟐.𝟓 𝒎/𝒔
𝟏𝟎 𝒔
=
𝟑.𝟓 𝒎/𝒔
𝟏𝟎 𝒔
=
0.35 m/s2
If you are roller-blading through the park and you come to a hill and your speed goes from 13 m/s to 6.5 m/s in 2
seconds, what is your acceleration?
𝑽𝒇 − 𝑽𝒊
𝒕𝒊𝒎𝒆
=
𝟔.𝟓 𝒎/𝒔− 𝟏𝟑 𝒎/𝒔
𝟐𝒔
=
−𝟔.𝟓 𝒎/𝒔
𝟐𝒔
2
= - 3.25 m/s
22. A remote control car is driving down the sidewalk at 2 m/s. It takes you 12 seconds to increase the speed to 10 m/s.
What is the car’s acceleration?
𝑽𝒇 − 𝑽𝒊
𝒕𝒊𝒎𝒆
=
𝟏𝟎 𝒎/𝒔− 𝟐 𝒎/𝒔
𝟏𝟐 𝒔
=
𝟖 𝒎/𝒔
𝟏𝟐 𝒔
=
0.67 m/s2
23. A truck is driving at 140 m/s but gets into traffic and slows down to 25 m/s in 10 seconds. What is the truck’s
acceleration?
𝑽𝒇 − 𝑽𝒊
𝒕𝒊𝒎𝒆
=
𝟐𝟓 𝒎/𝒔− 𝟏𝟒𝟎 𝒎/𝒔
𝟏𝟎 𝒔
=
−𝟏𝟏𝟓 𝒎/𝒔
𝟏𝟎 𝒔
=
-11.5 m/s2
Use one of the following words to complete the sentences:
Increases
decreases
remains constant
24. If mass is constant, as force increases, acceleration increases
25. If the force is constant, as mass increases, acceleration decreases
26. With what force will a car hit a tree if the car has a mass of 3,000 kg and it is accelerating at a rate of 2 m/s 2?
F=m*a
m = 3000 kg
a = 2 m/s2
F = 6,000 N
27. A 10 kg bowling ball would require what force to accelerate it down an alleyway at a rate of 3 m/s2?
F=m*a
m = 10 kg
a = 3 m/s2
F = 30 N
28. With what force will a falling rock hit the ground with if it accelerates at 9.8 m/s2? The rock has a mass of 5 kg.
F=m*a
m = 5 kg
a = 9.8 m/s2
F = 49 N
29. How much force is needed to accelerate a 7500 kg F-4 Tomcat fighter jet off the deck of an aircraft carrier at 9 m/s 2?
F=m*a
m = 7500 kg
a = 9 m/s2
F = 67,500 N
30. A 55 kg ice skater would require what force to accelerate her to spin at a rate of 12.5 m/s2?
F=m*a
m = 55 kg
a = 12.5 m/s2
F = 687.5 N
 Newton’s Three Laws of Motion
31. First Law : an object at rest will stay at rest & an object in motion will stay in motion unless an
outside force is applied.
32. Second Law:
if mass increases, acceleration decreases
If force increases, acceleration increases
F = MA
33. Third Law: for every action there is an equal and opposite reaction