Download What is the relationship between impulse and momentum

Impulse and Changes in Momentum Part I of 2
Newton’s law of Motion
Active Physics
Name: ______________________________Grade:___ Class Period: ___ Date:____________
Essential Question: What is the relationship between impulse and momentum? PSc.1.1.2
Instructions: Study pp. 118-120 and answer the following questions.
1. What is an impulse? (p. 113)
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2. What does it take to stop a moving car? ( p. 118)
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3. What law can help you identify the amount of force needed to stop a moving object?
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4. Copy the concept map ( flowchart ) and answer the following questions a, b, and c.
DO NOT FORGET THE ARROWS. ( p. 118)
a. What is the equation/formula for force ( F)? Write the symbol and meaning of each variable.
F=
m=
a=
b. What is the equation for acceleration ( a )? Write the symbol and meaning of each variable.
a=
Δv =
Δt =
c. What is the equation for change in velocity (Δv)? the symbol and meaning of each variable.
Δv =
vf =
vi =
5. What variables do you need to calculate force ( F) using Newton’s Second Law?
Sample Problem: A moving car has a forward velocity of 15 m/s. Stopping the car gives it a final
velocity of 0 m/s. ( p. 118 )
a. What is the change in velocity of the car?
b. What do you call any change in velocity?
c. What is the acceleration ( a) of the car if the change in velocity occurs in 3 seconds?
Show the solution.
d. If the car had stopped in 0.5 seconds, what would be the acceleration?
Show the solution.
e. According to Newton’s Second Law of Motion, what causes all changes in acceleration ( a)?
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e. What are the possible unbalanced outside forces that stopped the car?
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f. If the car has mass ( m) of 1000 kg., what would be the unbalanced force ( F) for the acceleration
( a) of -5m/s? Use the equation/formula for force ( F) to show your solution.
g. f. If the car has mass ( m) of 1000 kg., what would be the unbalanced force ( F) for the
acceleration ( a) of -30m/s? Use the equation/formula for force ( F) to show your solution.
h. What does the negative ( -) sign mean in terms of force ( F) and acceleration ( a)?
It is not a sign of quantity!
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Impulse and Changes in Momentum Part 2 of 2
Newton’s law of Motion
Active Physics
Name: ______________________________Grade:___ Class Period: ___ Date:____________
Essential Question: What is the relationship between impulse and momentum? PSc.1.1.2
Instructions: Study pp. 118-120 and answer the following questions.
1. What is momentum? ( p. 119)
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2. What is the equation/formula for momentum ( p)? Write the meaning of each variable.
F=
m=
v=
3. What does the impulse/momentum equation tells you?
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4. Complete the impulse/momentum concept map ( flow chart ) DO NOT FORGET THE ARROWS.
Where:
Δp is impulse or change in momentum
Δt is ____________________________
Δv is ____________________________
F is force
3m/s
5. Newton’s Second Law Explained: Whether you land on soft grass or hard concrete, your
change in velocity will be identical. Explain this. Think!
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0m/s
6. Why do prefer to land on soft grass rather than on hard concrete? Use the concept of
impulse/momentum to answer this question. Why is the force on your legs lesser when you
land on soft grass? Think! ( read p. 119-120)
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7. Why do you have slower change in acceleration when landing on soft grass?
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8. What is the relationship between changing acceleration so fast and being hurt? Think!
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9. How does Newton’s law explain your choice of landing on soft grass rather than on hard concrete?
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10. How is the change in momentum or Δp of an object always identical?
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11. Study the MOMENTUM/IMPULSE table and answer the following questions.
Change in value of
momentum Δp
150 kg m/s
150 kg m/s
150 kg m/s
150 kg m/s
150 kg m/s
a. Explain this equation.
FΔt = Δp
Force
50 N
75 N
150 N
1,500 N
15,000 N
Change in Time or Δt
3s
2s
1s
0.1s
0.01s
F Δt
150 kg m/s
150 kg m/s
150 kg m/s
150 kg m/s
150 kg m/s
Where:
Δp is impulse or change in momentum
Δt is change in time
Δv is change in velocity
F is force
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b. What happens to the amount of time (Δt) as the force increases?
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c. What happens to the amount of time (Δt) as the force decreases?
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d. Cite personal experiences where Newton’s Second Law of Motion is at work?
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