Transcript Changes-in-Motion-Review

Force and Motion Review
1. What is the formula for calculating work?
Work = Force X Distance
2. What is the formula for calculating speed?
Speed = Distance/Time
3. What is the formula for calculating force
Force = Mass X Acceleration
W
F D
D
S t
F
M A
4. Calculate the amount of work done when a
box weighing 8 Newtons is moved 20 meters.
W= 8 X 20
Work = 160 J
5. Calculate the amount of work done when a
girl weighing 50 Newtons moves up stairs 5.3
meters high.
265 j
6. Calculate the amount of work done when a
car weighing 100 Newtons moves 40 meters.
4000 j
7. How do you know when no work has
occurred?
If the object has not moved no work has been
done.
8. Calculate the speed of a car that traveled 300
miles in 5 hours.
60 mph
9. Calculate the speed of a plane that traveled
1200 miles in 2 hours.
600 mph
10. Phil the slug crept along at a speed of .3
m/hr. How far did he travel in 5 hours?
1.5 meters
11. What is the speed of a runner, if he runs
26.1 miles in 5 hours? 5.22 mph
12. A fire truck took 30 minutes to get to a blaze
45 miles away. What was the speed?
90 mph or 1.5 m/min
13. Ms. Piggy runs 1.5 meters in 5 min. What
was her speed? .3 m/min
14. Emily ran the 400 meter dash in 2 minutes.
What is Emily’s speed? 200 m/min (3.3 m/sec)
15. Calculate the force a car exerts when it
moves its mass of 100 kg with an acceleration of
200 m/s2.
20,000 N
16. Calculate the force a man exerts on a diving
board when he dives if his mass is 5 kg and
the acceleration was 10 m/s2. 50N
17. A wooden block weighing 8 kilograms is
moved with a force of 30 newtons. What is the
acceleration of the block of wood?
3.75m/s/s
18. Draw examples of an unbalanced force.
19. Draw examples of a balanced force.
20. Draw examples of Newton’s 1st Law of
Motion.
21. Draw examples of Newton’s 2nd of Motion.
22. Draw examples of Newton’s
3rd Law of Motion.
23. The resistance to any motion is __________
friction
24. If you want to push an object and it does not
balanced
move then, the forces are ______________.
25. If you apply a force of 600 N onto an object,
what force does the object apply to you?
600
_______N
26. The force pulling on every object is
gravity
__________________
27. How would you describe gravitational forces
in deep space? ______________________
Gravity is less
F1=20N
F2=20N
0N
28. What is the Net Force =______________
F2=20N
29. Which direction will the apple move?
West
F1=20N
30. Which direction will
the apple move?
SouthWest F2=40N
31. Smaller masses need more/less force to
move
32. Larger masses need more/less force to move.
33. Which requires less force to move, a 200 kg
crate or a 500 kg crate?
200 kg
34. Use your formula chart to calculate which of
these situations the most work is being done.
A. Jeff raises a box that weighs 4 newtons to
28
Joules
a height of
7 meters
B. David raises a block that weighs 3
Joules
newtons to a 24
height
of 8 meters
C. Will raises a book that weighs 2 newtons
to a height 20
of 10
meters
Joules
D. Zach raises a ball that weighs 5 newtons
to a height of 5 meters
25 Joules
35.Why do we wear seatbelts?
(be specific and use your knowledge of
Newton’s Laws to explain)
Inertia keeps us moving and the seat belt
applies a force to stop that motion.
40
Distance (feet)
35
30
25
20
15
10
5
0
0
5
10
15
Time (secs)
36. When is the object experiencing a balanced
force?When
______________
the line is straight
37. When is the object experiencing unbalanced
forces?When
________________
the line changes direction
38. When is the object not moving?
________________
When
the line is flat, 2 to 7 sec.
39. Describe Slope B:
A
B
Going forward for 10
minutes at a speed of
40 m per min.,
stopped for 10
minutes, went
forward for another
10 minutes at a speed
of 80 m per min.
39. Rollercoaster:
Greatest
Potential Energy
Greatest
Kinetic
Energy
40. Pendulum
Greatest
Potential
Energy
Greatest
Kinetic
Energy
Greatest
Potential
Energy
41.What is the Law of Conservation of
Energy?
energy is neither created nor destroyed
In 1842, Julius Robert Mayer discovered
the Law of Conservation of Energy, it now
called the First Law of Thermodynamics…