Oct. 23, 2012 AGENDA: 1 – Bell Ringer 2 – Velocity Time Graphs 3 – Review of Quiz 2 Today’s...
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Transcript of Oct. 23, 2012 AGENDA: 1 – Bell Ringer 2 – Velocity Time Graphs 3 – Review of Quiz 2 Today’s...
Oct. 23, 2012
AGENDA:1 – Bell Ringer2 – Velocity Time
Graphs3 – Review of Quiz 2
Today’s Goal:Students will be able to construct velocity vs. time graphs & explain that acceleration is the change in velocity over time.Homework
1. Pages 7-8
CHAMPS for Bell Ringer
C – Conversation – No Talking H – Help – RAISE HAND for questionsA – Activity – Solve Bell Ringer on
binder paper. Homework out on desk
M – Materials and Movement – Pen/Pencil, Notebook or Paper
P – Participation – Be in assigned seats, work silently
S – Success – Get a stamp! I will collect!
Tuesday, Oct. 23rd (p. 15)
Objective: Students will be able to construct velocity vs. time graphs & explain that acceleration is the change in velocity over time.
Bell Ringer:1. When you are stopped what
is your velocity?2. When your acceleration is
positive describe what is happening to your velocity.
3. When your acceleration is negative describe what is happening to your velocity.
4 MINUTES REMAINING…
Tuesday, Oct. 23rd (p. 15)
Objective: Students will be able to construct velocity vs. time graphs & explain that acceleration is the change in velocity over time.
Bell Ringer:1. When you are stopped what
is your velocity?2. When your acceleration is
positive describe what is happening to your velocity.
3. When your acceleration is negative describe what is happening to your velocity.
3 MINUTES REMAINING…
Tuesday, Oct. 23rd (p. 15)
Objective: Students will be able to construct velocity vs. time graphs & explain that acceleration is the change in velocity over time.
Bell Ringer:1. When you are stopped what
is your velocity?2. When your acceleration is
positive describe what is happening to your velocity.
3. When your acceleration is negative describe what is happening to your velocity.
2 MINUTES REMAINING…
Tuesday, Oct. 23rd (p. 15)
Objective: Students will be able to construct velocity vs. time graphs & explain that acceleration is the change in velocity over time.
Bell Ringer:1. When you are stopped what
is your velocity?2. When your acceleration is
positive describe what is happening to your velocity.
3. When your acceleration is negative describe what is happening to your velocity.
1minute Remaining…
Tuesday, Oct. 23rd (p. 15)
Objective: Students will be able to construct velocity vs. time graphs & explain that acceleration is the change in velocity over time.
Bell Ringer:1. When you are stopped what
is your velocity?2. When your acceleration is
positive describe what is happening to your velocity.
3. When your acceleration is negative describe what is happening to your velocity.
30 Seconds Remaining…
Tuesday, Oct. 23rd (p. 15)
Objective: Students will be able to construct velocity vs. time graphs & explain that acceleration is the change in velocity over time.
Bell Ringer:1. When you are stopped what
is your velocity?2. When your acceleration is
positive describe what is happening to your velocity.
3. When your acceleration is negative describe what is happening to your velocity.
BELL-RINGER TIME IS
UP!
Tuesday, Oct. 23rd (p. 15)
Objective: Students will be able to construct velocity vs. time graphs & explain that acceleration is the change in velocity over time.
Bell Ringer:1. When you are stopped what
is your velocity?2. When your acceleration is
positive describe what is happening to your velocity.
3. When your acceleration is negative describe what is happening to your velocity.
Shout Outs
Period 5 – Christopher JordanPeriod 7 – Deon Burgess
Oct. 23, 2012
AGENDA:1 – Bell Ringer2 – Velocity Time
Graphs3 – Review of Quiz 2
Today’s Goal:Students will be able to construct velocity vs. time graphs & explain that acceleration is the change in velocity over time.Homework
1. Pages 7-8
Week 7
Weekly AgendaMonday – Review & Quiz 3Tuesday – Velocity Time GraphsWednesday – Metric SystemThursday – Metric System LabFriday – Quiz 4
Unit Test in 2 weeks!
CHAMPS for Problems p. 5-8
C – Conversation – No Talking unless directed to work in groups
H – Help – RAISE HAND for questionsA – Activity – Solve Problems on Page
5-8M – Materials and Movement –
Pen/Pencil, Packet Pages 5-8P – Participation – Complete Page 5-8S – Success – Understand all
Problems
Velocity Time Graphs (p. 5)
Exercise 1: The diagram shows a velocity-time graph describing the motion of a car.
0
2
4
6
8
10
12
14
0 5 10 15 20
time (s)
velo
city
(m
/s)
i. Describe the motion of the car during :
part AB = ___________ part BC = ______________ part CD = ______________
Write in A, B, C, D
A
B C
D
Velocity Time Graphs (p. 5)
Exercise 1: The diagram shows a velocity-time graph describing the motion of a car.
0
2
4
6
8
10
12
14
0 5 10 15 20
time (s)
velo
city
(m
/s)
i. Describe the motion of the car during :
part AB = Positive Acceleration part BC = ______________ part CD = ____________
Velocity Time Graphs (p. 5)
0
2
4
6
8
10
12
14
0 5 10 15 20
time (s)
velo
city
(m
/s)
i. Describe the motion of the car during :
part AB = Positive Acceleration part BC = Constant Velocity part CD = Negative Acceleration
Velocity Time Graphs (p. 5)
Exercise 1: The diagram shows a velocity-time graph describing the motion of a car.
0
2
4
6
8
10
12
14
0 5 10 15 20
time (s)
velo
city
(m
/s)
ii. What is the distance / displacement covered in the
first 5 seconds?
Velocity Time Graphs (p. 5)
Exercise 1: The diagram shows a velocity-time graph describing the motion of a car.
0
2
4
6
8
10
12
14
0 5 10 15 20
time (s)
velo
city
(m
/s)
ii. What is the distance / displacement covered in the
first 5 seconds?
Distance / displacement is area under the
curve!
Velocity Time Graphs (p. 5)
Exercise 1: The diagram shows a velocity-time graph describing the motion of a car.
0
2
4
6
8
10
12
14
0 5 10 15 20
time (s)
velo
city
(m
/s)
ii. What is the distance / displacement covered in the
first 5 seconds?
Distance / displacement is area under the
curve!
Velocity Time Graphs (p. 5)
Exercise 1: The diagram shows a velocity-time graph describing the motion of a car.
0
2
4
6
8
10
12
14
0 5 10 15 20
time (s)
velo
city
(m
/s)
ii. What is the distance / displacement covered in the
first 5 seconds?
Area = base * height / 2 = (5 s)(10 m/s)/2 = 25 m
Distance / displacement is area under the
curve!
Velocity Time Graphs (p. 5)
Exercise 1: The diagram shows a velocity-time graph describing the motion of a car.
0
2
4
6
8
10
12
14
0 5 10 15 20
time (s)
velo
city
(m
/s)
iii. What is the acceleration during this time?
a = (vf – vi) Δt
Acceleration is the slope
a = (vf – vi)/Δt
(0s, 0 m/s)
(5s, 10 m/s)
Velocity Time Graphs (p. 5)
Exercise 1: The diagram shows a velocity-time graph describing the motion of a car.
0
2
4
6
8
10
12
14
0 5 10 15 20
time (s)
velo
city
(m
/s)
iii. What is the acceleration during this time?
a = (vf – vi) = (10 m/s – 0 m/s) = 2 m/s2
Δt 5 – 0 s
Acceleration is the slope
(0s, 0 m/s)
(5s, 10 m/s)
Velocity Time Graphs (p. 5)
Exercise 2: The velocity-time graph shown below shows a lift climbing from the ground floor to the top of a building.
i. At which point, A, B or C is the lift on the ground floor? ______ ii. At which point is it travelling fastest? _______ iii. What is its maximum velocity in m/s? __________ iv. How long does it take to reach this velocity? _______
0123456789
10
0 1 2 3 4 5 6 7
time (s)
velo
city
(m
/s)
A
B
C
Velocity Time Graphs (p. 5)
Exercise 2: The velocity-time graph shown below shows a lift climbing from the
ground floor to the top of a building. i. At which point, A, B or C is the lift on the ground floor? A ii. At which point is it travelling fastest? _______ iii. What is its maximum velocity in m/s? __________ iv. How long does it take to reach this velocity? _______
0123456789
10
0 1 2 3 4 5 6 7
time (s)
velo
city
(m
/s)
A
B
C
Velocity Time Graphs (p. 5) i. At which point, A, B or C is the lift on the ground floor? A ii. At which point is it travelling fastest? B iii. What is its maximum velocity in m/s? __________ iv. How long does it take to reach this velocity? _______
0123456789
10
0 1 2 3 4 5 6 7
time (s)
velo
city
(m
/s)
A
B
C
Velocity Time Graphs (p. 5)
Exercise 2: The velocity-time graph shown below shows a lift climbing from the ground floor to the top of a building.
i. At which point, A, B or C is the lift on the ground floor? A ii. At which point is it travelling fastest? B iii. What is its maximum velocity in m/s? 10 m/s iv. How long does it take to reach this velocity? _______
0123456789
10
0 1 2 3 4 5 6 7
time (s)
velo
city
(m
/s)
A
B
C
Velocity Time Graphs (p. 5)
Exercise 2: The velocity-time graph shown below shows a lift climbing from the ground floor to the top of a building.
i. At which point, A, B or C is the lift on the ground floor? A ii. At which point is it travelling fastest? B iii. What is its maximum velocity in m/s? 10 m/s iv. How long does it take to reach this velocity? 5 s
0123456789
10
0 1 2 3 4 5 6 7
time (s)
velo
city
(m
/s)
A
B
C
During part BC, the lift decelerates to stop at C, the top of the building. How long did the journey take? ________________
Velocity Time Graphs (p. 5)
i. At which point, A, B or C is the lift on the ground floor? A ii. At which point is it travelling fastest? B iii. What is its maximum velocity in m/s? 10 m/s iv. How long does it take to reach this velocity? 5 s v. During part BC, the lift decelerates
to stop at C, the top of the building. How long did the journey take? 2 seconds for part BC, 7 seconds total
0123456789
10
0 1 2 3 4 5 6 7
time (s)
velo
city
(m
/s)
A
B
C
Velocity Time Graphs (p. 6)
1. What is the acceleration between t = 0s and t = 2s?
Velocity Time Graphs (p. 6)
1. What is the acceleration between t = 0s and t = 2s?
a = (vf – vi) = (1 m/s – 0 m/s) = 1/2 m/s2
Δt 2 – 0 s
Velocity Time Graphs (p. 6)
2. What is the acceleration between t = 2s and t = 4s?
Velocity Time Graphs (p. 6)
2. What is the acceleration between t = 2s and t = 4s?
a = (vf – vi) = (3 m/s – 1 m/s) = 2 m/s2
Δt 4 – 2 s
Velocity Time Graphs (p. 6)
3. What is the acceleration between t = 4s and t = 5s?
Velocity Time Graphs (p. 6)
4. What is the acceleration between t = 5s and t = 6s?
Velocity Time Graphs (p. 6)
5. Is the velocity increasing or decreasing?
6. Is the acceleration positive or negative?
7. Is the acceleration increasing or decreasing?
Velocity Time Graphs (p. 6)
5. Is the velocity increasing or decreasing? Increasing
6. Is the acceleration positive or negative?Positive
7. Is the acceleration increasing or decreasing?Increasing
Quiz Review (p. 4)
Step 1: Read the Problem, underline key quantitiesStep 2: Assign key quantities a variableStep 3: Identify the missing variableStep 4: Choose the pertinent equation:Step 5: Solve for the missing variable.Step 6: Substitute and solve.
Quiz Review (p. 4)
5. If a ball rolls down a ramp with a starting velocity of 0 m/s and a final velocity of 6 m/s and
it takes a total of 1.4 seconds, what is the acceleration?
Quiz Review (p. 4)
5. If a ball rolls down a ramp with a starting velocity of 0m/s and a final velocity of 6m/s and it
takes a total of 1.4 seconds, what is the acceleration?
Step 1: Read the Problem, underline key quantities
Quiz Review (p. 4)
5. If a ball rolls down a ramp with a starting velocity of 0m/s and a final velocity of 6m/s and it
takes a total of 1.4 seconds, what is the acceleration?
Step 1: Read the Problem, underline key quantities
Quiz Review (p. 4)
5. If a ball rolls down a ramp with a starting velocity of 0m/s and a final velocity of 6m/s and it
takes a total of 1.4 seconds, what is the acceleration?
Step 2: Assign key quantities a variable
Solving Kinematics Problems
5. If a ball rolls down a ramp with a starting velocity of 0m/s and a final velocity of 6m/s and it
takes a total of 1.4 seconds, what is the acceleration?
Step 2: Assign key quantities a variable
vf = 6 m/svi = 0 m/sΔt = 1.4 s
Quiz Review (p. 4)
5. If a ball rolls down a ramp with a starting velocity of 0m/s and a final velocity of 6m/s and it
takes a total of 1.4 seconds, what is the acceleration?
Step 3: Identify the missing variable
vf = 6 m/svi = 0 m/sΔt = 1.4 s
Quiz Review (p. 4)
5. If a ball rolls down a ramp with a starting velocity of 0m/s and a final velocity of 6m/s and it
takes a total of 1.4 seconds, what is the acceleration?
Step 3: Identify the missing variable
vf = 6 m/svi = 0 m/sΔt = 1.4 sa = ?
Quiz Review (p. 4)
5. If a ball rolls down a ramp with a starting velocity of 0m/s and a final velocity of 6m/s and it
takes a total of 1.4 seconds, what is the acceleration?
Step 4: Choose the pertinent equation:
vf = 6 m/svi = 0 m/sΔt = 1.4 sa = ?
Δx = xf – xi v = Δx/Δt a = (vf – vi)/Δt
Quiz Review (p. 4)
5. If a ball rolls down a ramp with a starting velocity of 0m/s and a final velocity of 6m/s and it
takes a total of 1.4 seconds, what is the acceleration?
Step 4: Choose the pertinent equation:
vf = 6 m/svi = 0 m/sΔt = 1.4 sa = ?
Δx = xf – xi v = Δx/Δt a = (vf – vi)/Δt
Quiz Review (p. 4)
5. If a ball rolls down a ramp with a starting velocity of 0m/s and a final velocity of 6m/s and it
takes a total of 1.4 seconds, what is the acceleration?
Step 5: Solve for the missing variable
vf = 6 m/svi = 0 m/sΔt = 1.4 sa = ?
a = (vf – vi)/Δt
Quiz Review (p. 4)
5. If a ball rolls down a ramp with a starting velocity of 0m/s and a final velocity of 6m/s and it
takes a total of 1.4 seconds, what is the acceleration?
Step 6: Substitute and solve.
vf = 6 m/svi = 0 m/sΔt = 1.4 sa = ?
a = (vf – vi)/Δt = (6 m/s – 0 m/s)/1.4 s = 4.29 m/s2
Solving Kinematics Problems
Step 1: Read the Problem, underline key quantitiesStep 2: Assign key quantities a variableStep 3: Identify the missing variableStep 4: Choose the pertinent equation:Step 5: Solve for the missing variable.Step 6: Substitute and solve.
Quiz Review (p. 6)
6 . Brittany is driving her car and takes off from a stop light with an acceleration of 5m/s2 and
maintains a constant acceleration until her final velocity is 25m/s. How long did it take?
Quiz Review (p. 4)
6. Brittany is driving her car and takes off from a stop light with an acceleration of 5m/s2 and
maintains a constant acceleration until her final velocity is 25m/s. How long did it take?
Step 1: Read the Problem, underline key quantities
Quiz Review (p. 4)
6. Brittany is driving her car and takes off from a stop light with an acceleration of 5m/s2 and
maintains a constant acceleration until her final velocity is 25m/s. How long did it take?
Step 1: Read the Problem, underline key quantities
Quiz Review (p. 4)
6. Brittany is driving her car and takes off from a stop light with an acceleration of 5m/s2 and
maintains a constant acceleration until her final velocity is 25m/s. How long did it take?
Step 2: Assign key quantities a variable
Quiz Review (p. 4)
6. Brittany is driving her car and takes off from a stop light with an acceleration of 5m/s2 and
maintains a constant acceleration until her final velocity is 25m/s. How long did it take?
Step 2: Assign key quantities a variable
a = 5 m/s2
vf = 25 m/svi = 0 m/s
Quiz Review (p. 6)
6. Brittany is driving her car and takes off from a stop light with an acceleration of 5m/s2 and
maintains a constant acceleration until her final velocity is 25m/s. How long did it take?
Step 2: Assign key quantities a variable
a = 5 m/s2
vf = 25 m/svi = 0 m/s
Quiz Review (p. 4)
6. Brittany is driving her car and takes off from a stop light with an acceleration of 5m/s2 and
maintains a constant acceleration until her final velocity is 25m/s. How long did it take?
Step 3: Identify the missing variable
a = 5 m/s2
vf = 25 m/svi = 0 m/s
Quiz Review (p. 4)
6. Brittany is driving her car and takes off from a stop light with an acceleration of 5m/s2 and
maintains a constant acceleration until her final velocity is 25m/s. How long did it take?
Step 3: Identify the missing variable
a = 5 m/s2
vf = 25 m/svi = 0 m/sΔt = ?
Quiz Review (p. 4)
6. Brittany is driving her car and takes off from a stop light with an acceleration of 5m/s2 and
maintains a constant acceleration until her final velocity is 25m/s. How long did it take?
Step 4: Choose the pertinent equation a = 5 m/s2
vf = 25 m/svi = 0 m/sΔt = ?
Δx = xf – xi v = Δx/Δt a = (vf – vi)/Δt
Quiz Review (p. 4)
6. Brittany is driving her car and takes off from a stop light with an acceleration of 5m/s2 and
maintains a constant acceleration until her final velocity is 25m/s. How long did it take?
Step 4: Choose the pertinent equation a = 5 m/s2
vf = 25 m/svi = 0 m/sΔt = ?
Δx = xf – xi v = Δx/Δt a = (vf – vi)/Δt
Quiz Review (p. 4)
6. Brittany is driving her car and takes off from a stop light with an acceleration of 5m/s2 and
maintains a constant acceleration until her final velocity is 25m/s. How long did it take?
Step 4: Choose the pertinent equation a = 5 m/s2
vf = 25 m/svi = 0 m/sΔt = ?
Δx = xf – xi v = Δx/Δt a = (vf – vi)/Δt
Quiz Review (p. 4)
6. Brittany is driving her car and takes off from a stop light with an acceleration of 5m/s2 and
maintains a constant acceleration until her final velocity is 25m/s. How long did it take?
Step 5: Solve for the missing variable.a = 5 m/s2
vf = 25 m/svi = 0 m/sΔt = ?
Δx = xf – xi v = Δx/Δt a = (vf – vi)/Δt
Quiz Review (p. 4)
6. Brittany is driving her car and takes off from a stop light with an acceleration of 5m/s2 and
maintains a constant acceleration until her final velocity is 25m/s. How long did it take?
Step 5: Solve for the missing variable.a = 5 m/s2
vf = 25 m/svi = 0 m/sΔt = ?a = (vf – vi)/Δt
Quiz Review (p. 4)
6. Brittany is driving her car and takes off from a stop light with an acceleration of 5m/s2 and
maintains a constant acceleration until her final velocity is 25m/s. How long did it take?
Step 5: Solve for the missing variable.a = 5 m/s2
vf = 25 m/svi = 0 m/sΔt = ?Δt *a = Δt * (vf – vi)
Δt
Quiz Review (p. 6)
2. Brittany is driving her car and takes off from a stop light with an acceleration of 5m/s2 and
maintains a constant acceleration until her final velocity is 25m/s. How long did it take?
Step 5: Solve for the missing variable.a = 5 m/s2
vf = 25 m/svi = 0 m/sΔt = ?Δt *a = (vf – vi)
Quiz Review (p. 4)
6. Brittany is driving her car and takes off from a stop light with an acceleration of 5m/s2 and
maintains a constant acceleration until her final velocity is 25m/s. How long did it take?
Step 5: Solve for the missing variable.a = 5 m/s2
vf = 25 m/svi = 0 m/sΔt = ?Δt *a = (vf – vi)
a a
Quiz Review (p. 4)
6. Brittany is driving her car and takes off from a stop light with an acceleration of 5m/s2 and
maintains a constant acceleration until her final velocity is 25m/s. How long did it take?
Step 5: Solve for the missing variable.a = 5 m/s2
vf = 25 m/svi = 0 m/sΔt = ?Δt = (vf – vi)
a
Quiz Review (p. 4)
6. Brittany is driving her car and takes off from a stop light with an acceleration of 5m/s2 and
maintains a constant acceleration until her final velocity is 25m/s. How long did it take?
Step 6: Substitute and solve.a = 5 m/s2
vf = 25 m/svi = 0 m/sΔt = ?Δt = (vf – vi)
a
Quiz Review (p. 4)
6. Brittany is driving her car and takes off from a stop light with an acceleration of 5m/s2 and
maintains a constant acceleration until her final velocity is 25m/s. How long did it take?
Step 6: Substitute and solve.a = 5 m/s2
vf = 25 m/svi = 0 m/sΔt = ?Δt = (vf – vi) = (25 – 0 m/s) = 5 s
a 5 m/s2
Solving Kinematics Problems
Step 1: Read the Problem, underline key quantitiesStep 2: Assign key quantities a variableStep 3: Identify the missing variableStep 4: Choose the pertinent equation:Step 5: Solve for the missing variable.Step 6: Substitute and solve.
Quiz Review
If the average velocity of a car is 20 km/hr, how far can it travel in 3 hrs? Show ALL of the steps
we discussed in classStep 1: Read the Problem, underline key
quantities
Quiz Review
If the average velocity of a car is 20 km/hr, how far can it travel in 3 hrs? Show ALL of the steps
we discussed in classStep 1: Read the Problem, underline key
quantities
Quiz Review
If the average velocity of a car is 20 km/hr, how far can it travel in 3 hrs? Show ALL of the steps
we discussed in classStep 2: Assign key quantities a variable
Quiz Review
If the average velocity of a car is 20 km/hr, how far can it travel in 3 hrs? Show ALL of the steps
we discussed in classStep 2: Assign key quantities a variable
v = 45 km / hrΔt = 3 hrs
Quiz Review
If the average velocity of a car is 20 km/hr, how far can it travel in 3 hrs? Show ALL of the steps
we discussed in classStep 2: Assign key quantities a variable
v = 45 km / hrΔt = 3 hrs
Quiz Review
If the average velocity of a car is 20 km/hr, how far can it travel in 3 hrs? Show ALL of the steps
we discussed in classStep 3: Identify the missing variable
v = 45 km / hrΔt = 3 hrs
Quiz Review
If the average velocity of a car is 20 km/hr, how far can it travel in 3 hrs? Show ALL of the steps
we discussed in classStep 3: Identify the missing variable
v = 45 km / hrΔt = 3 hrs Δx = ?
Quiz Review
If the average velocity of a car is 20 km/hr, how far can it travel in 3 hrs? Show ALL of the steps
we discussed in class Step 4: Choose the pertinent equation:
v = 45 km / hrΔt = 3 hrs Δx = ?
Δx = xf – xi v = Δx/Δt a = (vf – vi)/Δt
Quiz Review
If the average velocity of a car is 20 km/hr, how far can it travel in 3 hrs? Show ALL of the steps
we discussed in class Step 4: Choose the pertinent equation:
v = 45 km / hrΔt = 3 hrs Δx = ?
Δx = xf – xi v = Δx/Δt a = (vf – vi)/Δt
Quiz Review
If the average velocity of a car is 20 km/hr, how far can it travel in 3 hrs? Show ALL of the steps
we discussed in class Step 5: Solve for the missing variable.
v = 45 km / hrΔt = 3 hrs Δx = ?
v = Δx/Δt
Quiz Review
If the average velocity of a car is 20 km/hr, how far can it travel in 3 hrs? Show ALL of the steps
we discussed in class Step 5: Solve for the missing variable.
v = 45 km / hrΔt = 3 hrs Δx = ?
Δt* v = Δx * Δt Δt
Quiz Review
If the average velocity of a car is 20 km/hr, how far can it travel in 3 hrs? Show ALL of the steps
we discussed in class Step 5: Solve for the missing variable.
v = 45 km / hrΔt = 3 hrs Δx = ?
Δt* v = Δx * Δt Δt
Quiz Review
If the average velocity of a car is 20 km/hr, how far can it travel in 3 hrs? Show ALL of the steps
we discussed in class Step 5: Solve for the missing variable.
v = 45 km / hrΔt = 3 hrs Δx = ?
Δt* v = Δx
Quiz Review
If the average velocity of a car is 20 km/hr, how far can it travel in 3 hrs? Show ALL of the steps
we discussed in class Step 6: Substitute and solve..
v = 45 km / hrΔt = 3 hrs Δx = ?
Δx= Δt* v = (20 km/hr)(3 hr) = 60 km