1. A motorcycle plus rider has a mass of 1000 kg. They travel inside a loop with a radius of 6 m. At the lowest point, the speed is 20 m/s. What force does the track exert on the motorcycle?

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1. A motorcycle plus rider has a mass of 1000 kg.
They travel inside a loop with a radius of 6 m.
At the lowest point, the speed is 20 m/s. What
force does the track exert on the motorcycle?
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F mv2/rF (1000) (20)2/(6)F 67,000 N
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2. Use the universal law of gravitation to find
the force between a 100 kg person standing on the
surface of the earth and the earth itself.
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F G m1m2/d2F (6.67 x 10-11) (6 x 1024)(100)
/ (6.4 x 106)2 F 980 N
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3. A uniform horizontal bar 1.00 m long is
pivoted at the left end. If the bar weighs 1.50
N, the clockwise torque is A) 0.50 m-N, B)
0.75 m-N, C) 1.00 m-N, D) 1.50 m-N.
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3. A uniform horizontal bar 1.00 m long is
pivoted at the left end. If the bar weighs 1.50
N, the clockwise torque is A) 0.50 m-N, B)
0.75 m-N, C) 1.00 m-N, D) 1.50 m-N.
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4. To produce rotational equilibrium in the bar
of question 4 what upward force must be exerted
0.75 m from the pivoted end? A) 0.50 N, B) 0.75
N, C) 1.00 N, D) 1.50 N.
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4. To produce rotational equilibrium in the bar
of question 4 what upward force must be exerted
0.75 m from the pivoted end? A) 0.50 N, B) 0.75
N, C) 1.00 N, D) 1.50 N.
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5. A uniform bar weighing 30.0 N is 5.00 m long.
Attached At the left end is a weight of 50.0 N,
and attached at the right end is a weight of 20.0
N. To prevent translational motion of the bar,
what upward force must be applied? A) 30.0 N,
B) 70.0 N, C) 80.0 N, D) 100.0 N
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5. A uniform bar weighing 30.0 N is 5.00 m long.
Attached At the left end is a weight of 50.0 N,
and attached at the right end is a weight of 20.0
N. To prevent translational motion of the bar,
what upward force must be applied? A) 30.0 N,
B) 70.0 N, C) 80.0 N, D) 100.0 N
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6. To prevent both translational and rotational
motion of the bar in number 5, a single upward
equilibrant force must be applied between the
A) left end and center of the the bar, but
nearer the left end, B) left end and center of
the bar, but nearer the center, C) right end
and center of the bar, but nearer the right end,
D) right end and center of the bar, but nearer
the center.
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6. To prevent both translational and rotational
motion of the bar in number 5, a single upward
equilibrant force must be applied between the
A) left end and center of the the bar, but
nearer the left end, B) left end and center of
the bar, but nearer the center, C) right end
and center of the bar, but nearer the right end,
D) right end and center of the bar, but nearer
the center.
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7. A beam 4.00 m long weighs 1400 N. Its center
of gravity is 1.50 m from the heavy end. At the
heavy end a weight of 1000 N is attached, while
at the light end there is a weight of 1350 N.
Find the magnitude and point of application of
the equilibrant force.
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Total downward force is 1400N 1000N 1350N
3750 N. CW 1400 x 1.5 2100 Nm1350 x 4
5400 Nm ------------- 7500
Nm CCW7500 Nm 3750 x length length 2 m
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8. The gravitational force between two masses is
36 N. What is the gravitational force if the
distance between them is tripled? a. 4.0 N b.
9.0 N c. 18 N d. 27 N
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8. The gravitational force between two masses is
36 N. What is the gravitational force if the
distance between them is tripled? a. 4.0 N b.
9.0 N c. 18 N d. 27 N
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9. If a net torque is applied to an object, that
object will experience which of the following?a.
a constant angular speed b. an angular
accelerationc. a constant moment of inertiad.
an increasing moment of inertia
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9. If a net torque is applied to an object, that
object will experience which of the following?a.
a constant angular speed b. an angular
accelerationc. a constant moment of inertiad.
an increasing moment of inertia
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10. Where should a force be applied on a lever
arm to produce the most torque?a. closest to
the axis of rotation b. farthest from the axis
of rotationc. in the middle of the lever arm d.
It doesnt matter where the force is applied.
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10. Where should a force be applied on a lever
arm to produce the most torque?a. closest to
the axis of rotation b. farthest from the axis
of rotationc. in the middle of the lever arm d.
It doesnt matter where the force is applied.
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11. Suppose a doorknob is placed at the center of
a door. Compared with a door whose knob is
located at the edge, what amount of force must be
applied to this door to produce the torque
exerted on the other door? a. one-half as
much b. two times as much c. one-fourth as
much d. four times as much
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11. Suppose a doorknob is placed at the center of
a door. Compared with a door whose knob is
located at the edge, what amount of force must be
applied to this door to produce the torque
exerted on the other door? a. one-half as
much b. two times as much c. one-fourth as
much d. four times as much
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12. If you cannot exert enough force to loosen a
bolt with a wrench, which of the following should
you do? a. Use a wrench with a longer
handle.b. Tie a rope to the end of the wrench
and pull on the rope. c. Use a wrench with a
shorter handle. d. You should exert a
force on the wrench closer to the bolt.
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12. If you cannot exert enough force to loosen a
bolt with a wrench, which of the following should
you do? a. Use a wrench with a longer
handle.b. Tie a rope to the end of the wrench
and pull on the rope. c. Use a wrench with a
shorter handle. d. You should exert a
force on the wrench closer to the bolt.
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13. A ball is whirled in a horizontal path on the
end of a string. Predict the path of the ball
when the string breaks, and explain your answer.
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The ball will go straight in the direction it was
going when the string broke due to the law of
inertia.
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14. How does the use of a machine alter the work
done on the object?
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It does not alter the work, it only alters the
force!