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Name ________________________________________Mods ________________________
STUDY GUIDE
UNIT 9-Newton’s Second Law: F=ma
Mon, Dec 14 Lab-
Dependence of Acceleration on Force
Complete graph
Tues, Dec 15 Go Over Graph and Lab ● finish lab report
● Read Section 5.1-5.3
and take notes in packet
● Watch Video and take
notes
Wed, Dec 16 Sample F=ma problem
Problem Set A
● Problem Set B
● Read Section 5.4-5.5
and take notes in packet
Thurs, Dec 17 Lab-Coefficient of Friction Watch Video and take notes
Fri, Dec 18 Problem Set C Study for test
Mon, Dec 21 Review for test Study for test
Tues, Dec 22 Test - Newton’s Second Law-F=ma
Wed, Dec 23 ½ day
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CP Physics
Reading Notes
Section 5.1-5.3
1. Write the equation for acceleration:
acceleration = __________
2. This chapter focuses on the _______________ of acceleration: _______________
3. To increase the _______________ of an object, you must _______________ the net
force acting on it
a. accelection is ______________ ______________ to net force
4. Acceleration depends on the _______________ being pushed
a. the same force applied to _______________ as much mass results in only
________________ the acceleration
b. for _______________ times the mass, _______________ the acceleration
results
c. For a given force, the acceleration produced is _______________
________________ to the mass
5. What is the equation for acceleration in terms of mass and force
acceleration = ____________________
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CP PHYSICS
PROBLEM SET A
F = ma EQUATIONS
F = m a Fg = m g
Key:
F = force (in N)
m = mass (in kg)
a = acceleration (in m/s2)
Fg = weight (in N)
g = acceleration due to gravity (10 m/s2)
1. What force is needed to accelerate a 2000 kg car at 15 m/s2?
2. A bowler imparts an acceleration of 40 m/s2 to a normal bowling ball during his release. Assuming the force
he gives the ball is 292 N, what is the mass of the ball in kg?
3. A pick-up truck has a mass of 1800 kg. If its engine is producing a force of 7200 N, what will the truck's
acceleration be?
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4. How much does a 0.25 kg wrench weigh on earth?
5. On one of Saturn's moons (Titan) the acceleration due to gravity is about 5 m/s2. How much would an astronaut
on Titan weigh if his mass is 85 kg?
6. On the planet Nebula, a 7 kg object weighs 35 N. What is the acceleration due to gravity on Nebula?
7. On Mars, g is equal to 6.4 m/s2 and an astronaut weighs 358.4 N. What is the mass of the astronaut?
ANSWERS: Not in Order (Some answers may be used more than once)
0.56 2.5 4 5 7.3 56 225 425 30,000 56,000
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PHYSICS
PROBLEM SET B
F=ma EQUATIONS
1. A 0.75 kg book is pushed across the table with an acceleration of 0.3 m/s2. What force is being applied to the
book?
2. During take off, a small 460 kg plane can undergo an acceleration of 6 m/s2. How much force the propeller is
supplying?
3. A 1500 kg sports car can accelerate at a rate of 5.2m/s2. What force does its engine give the car during this
acceleration?
4. On the launch pad, the Space Shuttle has a mass of 2,000,000 kg. In order to lift off, its engines must produce a
combined thrust of 29,250,000 N. What is the initial acceleration of the Space Shuttle?
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5. What is the weight of a 150 kg object (on Earth)?
6. What is the mass of a box that weighs 450 N?
7. What is the acceleration due to gravity on a planet where a 15 kg rock weighs 925 N?
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CP Physics
Reading Notes
Section 5.4-5.5
1. Friction is a _____________ like any other force and affects _______________
2. Friction acts on materials that are in ______________ with each other, and always acts
in the direction to _____________ motion
3. The force of friction between the surfaces depends on the _______________ in contact
and _______________ the surfaces are pressed together
4. _______________, which is the friction acting on something moving through
__________, is a very common form of fluid friction
5. The amount of _______________ per unit _____________ is called _______________
6. The equation for pressure is:
pressure = ____________________
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CP PHYSICS
PROBLEM SET C
FRICTION PROBLEMS
1.) What is the force of friction acting on a 453 N sled if the m between the sled and the floor is
0.23?
2.) What is the force of friction acting on a 67 kg box if the m between the box and the floor is
0.06?
3.) What is the acceleration of a 720 kg car that is being pushed by a truck with a force of
7,000N if the m between the tires and the road is 0.87?
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COEFFICIENT OF KINETIC FRICTION
Define Friction:
What factors affect friction?
What is the equation used to calculate friction?
Use algebra to solve for the coefficient of friction from the equation above:
Record the mass of one book = _______________ kg
Calculate the weight of one book:
Number of Books Normal Force (N) -
Weight
Kinetic Friction (N) – for
book sliding on table)
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2
3
4
5
6
7
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Describe the relationship between normal force (weight) and kinetic friction:
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Graph friction force vs normal force (weight). Calculate the slope of the best fit line.
What does this value represent?