Updated 5/27/07
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7.1 Circular Motion
Practice A, Centripetal Acceleration, pg 236
[1] 2.5m/s [2] 11 m/s [3] 1.5 m/s2 [4] 58.4 m
Ch 7 Review Q, pg 263: 8] 7.0 m/s 9] 2.7 m/s
Practice B, Centripetal Force, pg 238
[1] 29.6 kg [2] 40.0 m [3] 40.0 N [4] 35.0 m/s
Ch 7 Review Q, pg 263: [10a] 414 kg [b] 12.1 m/s [11] 62 kg
Section 7.1 Review Q, pg 239:
[2] 14 m/s [5] 1360 N
7.2 Newton’s Law of Universal Gravitation
Practice C, Gravitational Force, pg 242
[1] 0.692 m [2] 9.4x106
m = 9400 km
[3a] 651 N [b] 246 N [c] 38.5 N
Ch 7 Review Q, pg 264: [18] 2.50 m [19] 1.0x10-10
m = 0.10 nm
Section 7.2 Review Q, pg 247:
[3a] 636 N [b] 475 N [c] 678 N [d] 656 N
[5] 5.98x1024 kg
7.3 Motion in Space:
Skip
7.4 Torque & Simple Machines
Practice E, Torque pg 258
[1] 0.75 N●m [2a] 5.1 N●m
[b] 15.2 N●m [3] 133 N
Ch 7 Review Q, pg 265: [37] 26 N●m 38] 1.68x104
N●m
Section 7.4 Review Q, pg 261:
[5] 130 N [6] 2.7
[8] τ30
= 0 N●m,
τ25
= 43 N●m,
τ10
= -16 N●m,
τnet
= +27 N●m = clockwise
Mixed Review, pg 265: * = requires information from
previous chapters.
[39*] 12 m/s [40a] 4.34x1020 N [b]
1.99x1020 N [c] 3.52x1022
N
[41] 220 N [42] 200 N [43] 1800 N●m [44] -2200 N●m [45]
200 N
[46*] 63% [47] 72% [48] 6.4 m [49] skip
[50a] 0.965 m/s2 [b] 1330 N [c*] 0.0985
[51a] 6300 N●m [b] 550 N [52] 6.96x108 m
[53*] Ff = 6620 N, Fc = 7880 N [54] F = 6.6 N,
τmax
= 2.3 N●m
Standardized Test Prep, pg 268
[1] C [2] H [3] C [4] G [5] D [6] J [7] D [8] F [9] C
[10] G [11] G [12] H [13] A
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Use Loose Leaf, Answers Only
Terms may be used once or more or not at all.
Some statements have more than one term.
Angular
Speed Centrifugal Velocity Radian
Arc Length Centripetal Acceleration Tangential Acceleration
Area Centripetal Force Tangential Force
Axis of rotation Centripetal Velocity Tangential Velocity
Centrifugal Centripetal Uniform Circular Motion
Centrifugal Acceleration Circumference
Centrifugal Force Inertia
1 Acceleration of an object in uniform circular motion
due to its change in direction.
2 In circular motion, acceleration due to a change in
speed.
3 A center-directed force that causes an object to move
in a curved (sometimes circular) path.
4 In the tea cup amusement park ride it feels like a
force is pushing you outward but it is the force from the seat back that is
forcing you to move in a circle.
5 V2/R
6 The acceleration directed toward the center of a
curved path.
7 Away from the center point.
8 An object with a constant tangential speed.
9 The component of velocity tangent to the trajectory of
a projectile.
10 Line about which an object rotates or revolves.
11 The speed of an object that is tangent to the object’s
curved path.
12 The rate at which a body rotates around its axis.
13 Toward the center point.
14 # radians x Radius
15 Not
a force but the apparent or fictitious outward force on a
revolving body due to its inertia.
16 The tendency to move in a straight line path.
17 mV2/R
18 RPM●2πR
19 Rad/second.
20 2πR
21
πR2
22 Revolutions per second
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Ans Vocabulary 7.1
1 Centripetal
acceleration
2 Tangential acceleration
3 Centripetal Force
4 Centrifugal Force
5 Centripetal acceleration
6 Centripetal acceleration
7 Centrifugal
8 Uniform circular motion
9 Tangential velocity
10 Axis of rotation
11 Tangential velocity
12 Angular velocity
13 Centripetal
14 Arc Length
15 Centrifugal force
16 Inertia
17 Centripetal force
18 Tangential Velocity
19 Angular Speed
20 Circumference
21 Area
22 Angular Speed
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Terms may be used once or more or not at all.
Some statements have more than one term.
Center of Mass Law of Gravity,
Aristotle’s
Free Fall Law of Gravity, Newton’s
Free Fall Acceleration Mass, Gravitational
Gravitational Field Strength Mass, Inertial
Gravitational Force Universal Gravitational Constant
1 A measure of the resistance of an entity to a change
in its velocity.
2 G ME/RE2
3 Force per unit mass
4 m/s2
5 The center of a circle, sphere, or rectangle.
6 Fg = G M1 M2/d2
7 The force of mutual attraction between any two
objects.
8 Varies directly with the product of the masses and
inversely with the distance between their centers of mass.
9 An object can be treated as if all its mass
were concentrated here.
10 Measured by timing the fall of something.
11 9.81 m/s2
12 Equals free fall acceleration.
13 No experiment has ever been performed demonstrating it
is different form inertial mass.
14 Measured using a spring mechanism and an equation to
compare an unknown with a standard.
15 A measure of the strength of an object's interaction
with the gravitational field.
16 N/kg
17 g
18 Moving through air or space under the influence of
gravity only.
19 What goes up must come down.
20 G M1 M2/d2
21 6.67 x10-11
N●m2/kg2
22 The point of symmetry.
23 No lift, thrust, or drag.
24 Changes with location
25 Measured without any motion.
26 Measured using a balance mechanism to compare an
unknown with a standard.
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Ans Vocabulary 7.2
1 Mass,
Inertial 14 Mass, Inertial
2 Gravitational Force 15 Mass, Gravitational
& Law of Gravity, Newton’s
3 Gravitational Field Strength 16 Gravitational Field Strength
4 Free Fall Acceleration 17 Free Fall Acceleration
5 Center of Mass 18 Free Fall
6 Law of Gravity, Newton’s 19 Law of Gravity, Aristotle’s
7 Gravitational Force 20 Gravitational Force
8 Gravitational Force 21 Universal Gravitational Constant
& Law of Gravity, Newton’s
9 Center of Mass 22 Center of Mass
10 Free Fall Acceleration 23 Free Fall
11 Free Fall Acceleration 24 Free Fall Acceleration
Gravitational Field Strength
12 Gravitational Field Strength 25 Mass, Gravitational
13 Mass, Gravitational 26 Mass, Gravitational
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Linear Systems | Rotational
Systems
Mass (kg) | Moment of Inertia (I, kg●m2)
Speed (m/s) | Angular Speed (ω, radians/s)
Acceleration (m/s2) | Angular Acceleration (α,
radians/s2)
Force (N): F = ma | Torque (τ, N●m) τ = Iα
Kinetic Energy (mV2/2) | Iω2/2
Power = Force x Speed | Torque x Angular Speed
Moment of Inertia (I): a] The tendency of a rotating body
to resist change
in its rotating motion.
b] Similar to mass in linear systems.
Torque: a] A vector quantity.
b] The direction is perpendicular to both the radius from the
axis and to the force.
c] The perpendicular force x the distance to the pivot.
d] A rotational force which causes a change in rotational motion.
e] If you curl right hand fingers around the spin axis and in the
direction of spin, then your thumb points in the direction of torque.
See
http://hyperphysics.phy-astr.gsu.edu/hbase/tord.html
Compound Machine: Two or more connected simple machines.
Efficiency: a] Work Out x 100%
Work In
b] Never more than 100% or it will violate the law of conservation of energy.
Mechanical Advantage: a] A constant multiplier describing
a machine.
b] Force Out/Force In.
Ideal Mechanical Advantage:
a] The mechanical advantage of an ideal machine.
b] Din/Dout
Ideal Machine: a] A machine that is 100% Efficient.
b] A machine without friction.
Lever Arm: The distance from the applied force to the
pivot point.
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