1.
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If you drive west at 20 km/h for one hour, then drive east at 15 km/h for one hour, your net displacement will be
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| 5 km east. |
| 35 km west. |
| 35 km east. |
| 5 km west. |
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2.
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A 200-lb force is pulling on an object, as shown. The sign of the x and y components of the force are
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| x (positive), y (positive). |
| x (positive), y (negative). |
| x (negative), y (positive). |
| x (negative), y (negative). |
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3.
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Three boys each pull with a 20-N force on the same object. The resultant force will be
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| zero. |
| 20 N to the left. |
| 20 N up. |
| 20 N down. |
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4.
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Consider a plane flying with groundspeed Vg and airspeed Va in a wind with speed V. Which of the following relationships is true?
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| Vg will always equal Va + V |
| Vg can be greater than Va + V |
| Vg can be less than Va - V |
| Vg can have any value between Va + V and Va - V |
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5.
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Two vectors, R and S, are known: 
If vector S is subtracted from vector R, the vector T = R - S is
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6.
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Two vectors, R and S, are known:
If vector R is subtracted from vector S, the vector T = S - R is
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7.
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Two vectors, R and S, are known:
If vector S is added to the vector R, then the vector T = R + S is
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8.
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If the acceleration vector of a body is perpendicular to the velocity vector, which of the following must be true?
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| The speed is changing. |
| The direction is changing. |
| Both the speed and the direction are changing. |
| The direction is not changing. |
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9.
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A vector of magnitude 10 has an angle with the positive x-axis (East) of 120 degrees. What are its components?
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| 5 and 8.7 |
| -5 and 8.7 |
| 5 and -8.7 |
| -5 and -8.7 |
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10.
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A vector of magnitude 10 has an angle with the positive x-axis (East) of -60 degrees. What are its components?
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| 5 and 8.7 |
| -5 and 8.7 |
| 5 and -8.7 |
| -5 and -8.7 |
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11.
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A vector has components x=6 m and y=8 m. What is its magnitude and direction?
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| 10 m and 30 degrees |
| 14 m and 37 degrees |
| 10 m and 53 degrees |
| 14 m and 53 degrees |
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12.
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A vector has components x= -2 m and y=-2 m. What is its direction (angle with respect to East)?
|
| 45 degrees |
| 135 degrees |
| 225 degrees |
| -45 degrees |
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13.
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Three vectors have components (x,y):A=(2,3),B=(4,-7) and C=(-6,-3). What is the magnitude of the resultant vector (D=A+B+C)?
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| -7 |
| 17.7 |
| 15 |
| 7 |
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14.
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Three vectors have components (x,y):A=(2,3),B=(4,-7) and C=(-6,-3). What is the magnitude of the resultant vector (D=A-B-C)?
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| 13.6 |
| 15 |
| 52 |
| 7 |
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15.
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Suppose that several projectiles are fired on level ground. Which one will be in the air longest?
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| The one with the farthest range, R. |
| The one with the highest maximum elevation, h. |
| The one with the greatest initial velocity. |
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16.
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Which of the following does not affect the range of a projectile?
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| vo Initial Speed |
| qo Launch Angle |
| yo Initial Height |
| xo Initial Horizontal Position |
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17.
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Which of the following must be zero for a projectile to achieve its maximum range?
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| vxf |
| vyf |
| xf |
| yf |
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18.
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Which of the following must be zero for a projectile to be at its maximum height?
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| vxf |
| vyf |
| yf |
| xf |
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19.
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You hit a handball too hard and it lands, moving horizontally, on top of a roof. If its original velocity was vo at an angle q above the horizontal, then the velocity it lands on the roof with is
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| zero |
| vo sin q |
| vo cos q |
| 2vo |
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20.
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 You throw a pebble upward as shown, with a velocity vo at an angle theta, from a roof (at point J) h ft above the ground. If the pebble rises upward to h ft above the roof (to point K), then falls to the ground below (to point L), its speed when it hits the ground is
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| vo. |
| between vo and 2vo. |
| 2vo. |
| greater than 2vo. |
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21.
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Taking "up" as positive at the highest point, the acceleration of a projectile is
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| -9.8 m/s^2 |
| 0 m/s^2 |
| +9.8 m/s^2 |
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22.
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If the sum of two vectors equals zero, the magnitude of their difference is
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| equal to the magnitude of either one. |
| equal to twice the magnitude of either one. |
| less than twice the magnitude of either one. |
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23.
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A sailboat travelling with a speed of 4 knots heads directly up river against a 3 knot current. Its speed over ground is
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| 1 knot. |
| 7 knots. |
| 3 knots. |
| 5 knots. |
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24.
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A sailboat travelling with a speed of 4 knots heads directly down river with a 3 knot current. Its speed over ground is
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| 1 knot. |
| 3 knots. |
| 5 knots. |
| 7 knots. |
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25.
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A sailboat travelling with a speed of 4 knots heads directly across a river which has a 3 knot current. Its speed over ground is
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| 1 knot. |
| 3 knots. |
| 5 knots. |
| 7 knots. |
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26.
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Taking g=10 m/s2, if a jet plane does a loop-the-loop at a constant speed of 720 km/h and the radius of the circle is 1 km, what is the acceleration at the bottom?
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| g |
| 4 g |
| 6 g |
| 16 g |
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27.
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In the previous question what is the acceleration at the top?
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| g |
| 4 g |
| 6 g |
| 8 g |
