1.
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A stone, of mass m, is attached to a strong string and whirled in a vertical circle of radius r. At the exact top of the path the tension in the string is 3 times the stone's weight. The stone's speed at this point is given by
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| 2gr |
| 4gr |
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2.
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A stone, of mass m, is attached to a strong string and whirled in a vertical circle of radius r. At the exact bottom of the path the tension in the string is 3 times the stone's weight. The stone's speed at this point is given by
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| 2gr |
| 4gr |
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A stone is whirled in a vertical circle on a cord. Halfway up
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| the tension is towards the center of the circle and the net force is down. |
| the weight is down and the net force is towards the center of the circle. |
| the tension force is towards the center of the circle and the weight is down. |
| the weight and tension are in the same direction. |
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4.
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A roller coaster car is on a track that forms a circular loop in the vertical plane. If the car is to just maintain contact with the track at the top of the loop, what is the minimum value for its centripetal acceleration at this point?
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| g downward |
| g upward |
| 0.5 g downward |
| 2 g upward |
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5.
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 A girl attaches a rock to a string, which she then swings counter- clockwise in a horizontal circle. The string breaks at point P on the sketch, which shows a bird's-eye view (i.e., as seen from above). What path will the rock follow?
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| A |
| B |
| C |
| D |
| E |
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6.
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A packing crate slides down an inclined ramp at constant velocity. Thus we can deduce that
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| a frictional force is acting on it. |
| a net force is acting on it. |
| it may be accelerating. |
| Gravity is not acting on it. |
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7.
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Two objects are travelling in circular orbits. Object A is travelling at twice the velocity of object B in a circle with a diameter of twice that of B. The centripetal acceleration
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| of A and B are the same. |
| of A is twice that B. |
| of A is four times that of B. |
| of A is half that of B. |
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8.
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During the investigation of a traffic accident, police find skid marks 90 m long. They determine the coefficient of friction between the car's tires and the roadway to be 0.5 for the prevailing conditions. To find the speed of the car you must
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| know the mass of the car. |
| find the acceleration of the car. |
| know the mass of the car and find the acceleration of the car. |
| part of an ellipse. |
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9.
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An object is placed on an inclined plane. The angle of incline is gradually increased until the object begins to slide. The angle at which this occurs is q. What is the coefficient of static friction between the object and the plane?
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| sin q |
| cos q |
| tan q |
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10.
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 A toolbox, of mass M, is resting on a flat board. One end of the board is lifted up until the toolbox just starts to slide. The angle q that the board makes with the horizontal for this to occur depends on the
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| Mass, M. |
| Gravity is not acting on it. |
| normal force. |
| coefficient of static friction, m. |
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11.
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A ball of mass m is moving in a circle with uniform speed on a horizontal surface with friction at the end of a radial metal rod. The net force is
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| opposite the friction force. |
| in the direction of the friction force. |
| perpendicular to the surface. |
| is along the rod. |
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12.
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Which of the following does not belong with the others?
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| A car speeds up from 30 mph to 40 mph. |
| A car breaks from 20 mph to 0. |
| A race car rounds a curve at 120 mph. |
| A car coasts down a road at constant speed. |
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13.
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In the figure the force pulling block A down the plane at the left is
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| mgSin(q) |
| mgSin(f) |
| mgCos(q) |
| mgCos(f) |
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14.
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In the figure the normal force on block B is
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| mgSin(q) |
| mgSin(f) |
| mgCos(q) |
| mgCos(f) |
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15.
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In the figure in the above problem, assuming there is no friction, the net force acting to move the blocks together along the plains is
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| mgSin(f)-mgSin(q) |
| mgCos(f)-mgCos(q) |
| mgSin(f)+mgSin(q) |
| -mgSin(f)-mgSin(q) |
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16.
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If the acceleration of the blocks in the figure is 'a', which of the following formulae does not correctly give the tension T in the connecting cord.
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| mAa+mAgSin(q) |
| mBa+mBgSin(f) |
| (mA+mB)a+mAgSin(q) |
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17.
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If the angle q=45o and the angle f=30o and mass A is 5 kg what must be the mass B if the combination is not to accelerate?
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| 5 kg |
| 3.54 kg |
| 7.07 kg |
| 10 kg |
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18.
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In the previous question if A is 5 kg and B is 10 kg and q=45o what is f if the combination is not to accelerate.
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| 20.7o |
| 27.7o |
| 30.7o |
| 90o |
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19.
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In the figure the horizontal grey bar is massless, if the combination is accelerating upward at 1 m/s2 what is the tension, T1, in the upper cord?
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| 7 N |
| 6 N |
| 5 N |
| 4 N |
| 2 N |
| 1 N |
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20.
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In the figure the horizontal grey bar is massless, if the combination is accelerating upward at 1 m/s2 what is the tension, T2, in the purple cord?
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| 7 N |
| 6 N |
| 5 N |
| 4 N |
| 2 N |
| 1 N |
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21.
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If T1 in the figure in question 20 is 15 N what is T3?
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| 1.5 N |
| 2.5 N |
| 3.5 N |
| 4.5 N |
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22.
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In the figure the horizontal grey bar is massless, if the tension, T2, is 10 N what is the acceleration of the total combination ?
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| 1 m/s2 |
| 1.5 m/s2 |
| 2 m/s2 |
| 3 m/s2 |
| 4 m/s2 |
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23.
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 Each rope on the left supports the same weight, which has the greatest tension?
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| Red |
| Blue |
| Green |
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24.
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In question 23 which rope has the least tension?.
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| Red |
| Green |
| Blue |
| Can't be determined. |
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25.
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If the angle between the blue rope and the wall in question 23 is 20o, what is the tension in the rope?
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| 62 N |
| 52 N |
| 48 N |
| 22 N |
