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| 1 | When a rock is made to move in a circular path at the end of a string, an outward force is exerted on the rock. |
 | A) | True |
| B) | False |
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| 2 | If the string breaks in Question 1, centripetal acceleration will cause the rock to move inward. |
| A) | True |
| B) | False |
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| 3 | Centripetal and centrifugal forces have the same magnitudes but are opposite in directions; they don’t cancel because they act on different objects. |
| A) | True |
| B) | False |
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| 4 | When a car moves in a horizontal circle on a level road, the centripetal force is exerted by the tires. |
| A) | True |
| B) | False |
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| 5 | The maximum speed with which a car can negotiate a curve does not depend on the weight of the car. |
| A) | True |
| B) | False |
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| 6 | The period of revolution may be thought of as the number of complete revolutions per second. |
| A) | True |
| B) | False |
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| 7 | Just as a resultant force is needed to change the speed of a body, a resultant force is necessary to change its direction. |
| A) | True |
| B) | False |
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| 8 | Uniform circular motion is motion in which the linear speed changes at a constant rate. |
| A) | True |
| B) | False |
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| 9 | The formula for computing the banking angle also applies for the angle that the cord makes with the vertical for a conical pendulum. |
| A) | True |
| B) | False |
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| 10 | If two masses are separated by twice the distance, they will experience one-half the gravitational attraction. |
| A) | True |
| B) | False |
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| 11 | A ball is tied to a string and swung in a horizontal circle. When the string breaks, the ball will follow a path that is |
| A) | toward the center |
| B) | away from the center |
| C) | at a tangent to its circular path |
| D) | none of these |
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| 12 | The force exerted on the ball in Question 11 is a |
| A) | centrifugal force |
| B) | centripetal force |
| C) | gravitational force |
| D) | fictitious force |
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| 13 | A body traveling in a circular path at constant speed |
| A) | has an outward acceleration |
| B) | has inward acceleration |
| C) | has constant velocity |
| D) | is not accelerated |
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| 14 | An object makes one complete revolution in 0.5 s. Its frequency is |
| A) | 2 s |
| B) | 5 rev/s |
| C) | 2 rev/s |
| D) | 0.5 rev/s |
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| 15 | An object swings at the end of a string in uniform circular motion. Which of the following changes would not cause an increased centripetal force? |
| A) | A longer string |
| B) | A shorter string |
| C) | A greater linear speed |
| D) | A larger mass |
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| 16 | The linear speed of an object swinging in a circular path of radius 2 m with a frequency of 5 rev/s is |
| A) | 2 Π m/s |
| B) | 20 Π m/s |
| C) | 4 Π m/s |
| D) | 10 Π m/s |
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| 17 | The centripetal acceleration of a 2-kg mass swinging in a 0.4-m radius with a linear speed of 4 m/s is |
| A) | 4 m/s² |
| B) | 40 m/s² |
| C) | 10 m/s² |
| D) | 20 m/s² |
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| 18 | An 8-kg ball is swung in a horizontal circle by a cord of length 2 m. If the period is 0.5 s, the tension in the cord is approximately |
| A) | 264 N |
| B) | 202 N |
| C) | 1200 N |
| D) | 2527 N |
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| 19 | The banking angle for a curve of radius 400 ft for a speed of 60 mi/h should be approximately |
| A) | 31° |
| B) | 16° |
| C) | 26° |
| D) | 37° |
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| 20 | The gravitational constant is 6.67 x 10-11 N * m²/kg². What is the gravitational force between two 4-kg balls separated by 0.2 m? |
| A) | 5.34 x 10-7 N |
| B) | 2.67 x 1-8 N |
| C) | 1.33 x 10-8 N |
| D) | 6.67 x 10-8 N |
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| 21 | Uniform circular motion is motion in which there is no change in but only a change in . |
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| 22 | The is the number of revolutions per unit of time, whereas the is the time for one revolution. |
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| 23 | For a body moving in a horizontal circle, doubling the linear speed has the effect of increasing the centripetal acceleration by a factor of . |
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| 24 | The gravitational force between two particles is directly proportional to the product of their and inversely proportional to the of the between them. |
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| 25 | The force required to keep mass moving in a circular path at constant speed v is called the force and has a magnitude equal to , where R is the radius of the circle. |
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| 26 | The proper banking angle θ to eliminate the necessity for a frictional force is given by the relation , where v is the velocity, R is the radius of the curve, and g is the acceleration due to gravity. |
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| 27 | Whenever the centripetal force acts on an object, there is an equal and opposite force exerted by the object. |
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| 28 | When a curve is not banked, the centripetal force is provided by . |
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| 29 | The speed is the minimum speed needed to maintain circular motion in a vertical plane. |
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| 30 | The correct set of USCS units for the gravitational constant is . |