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1. A heavy crate falls from a high
flying airplane just as it flies directly above a shiny
Black Lexus parked in a car lot. The plane moves in the
leftward direction. Relative to the Lexus, where will the crate
crash? |
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a. on top the Lexus |
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b. at a point to the left of the
Lexus |
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c. at a point to the right of
the Lexus |
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d nota |
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2. In the previous problem, if the
airplane flies 50.0 m high, how long does it take the crate to hit
the ground? Choose the closest answer to your computation. |
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a. 2.3 seconds |
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b. 3.2 seconds |
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c. 1.0 second |
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3. Suppose the airplane in the previous problem
was flying at 30.0 m/s. Where does the crate land? |
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a. on top of the Lexus |
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b. about 96 m from the Lexus |
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c. about 69 m from the
Lexus |
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4. In the absence of air resistance,
the horizontal component VH of a projectile is
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a. constant |
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b. is not constant
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5. True or False. If you fire a
rifle at a distant target at the same vertical height as the gun,
to hit the target you should aim exactly at the target.
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a. True |
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b. False |
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6. A projectile is fired straight
upward with speed 1000 m/s . What is the speed when the projectile
reaches the top of the trajectory? |
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a. 1000 m/s |
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b. 100 m/s |
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c. nota |
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7. A projectile is fired with
speed 1410 m/s at an angle of 45 0 with the horizontal.
What is the horizontal component VH of the projectile?
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a.1000 m/s |
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b.100 m/s |
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c. 0 m/s |
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8. A NASA spacecraft orbits
closely in a circle around the Moon. The orbital speed is
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a. greater than 8 km/s
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b. less than 8 km/s
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c. equal to 8 km/s
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d. nota |
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9. What will be the speed of a
spacecraft in close circular orbit around a 20 m asteroid?
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a. greater than 8 km/s
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b. equal to 8 km/s
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c. nota |
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10. True or False. If a
satellite moves in a circular orbit, during its motion its kinetic
energy changes.
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a. True |
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b. False |
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11. True or False. If a
satellite moves in an elliptical orbit, during its motion its kinetic
energy does not change. |
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a. True |
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b. False |
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12. True or False. If a
satellite moves in an elliptical orbit, during its motion its potential
energy does not change. |
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a. True |
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b. False |
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13. A satellite moves in an
elliptical orbit around a planet. During its motion, its kinetic
energy is greatest |
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a. at a point nearest the planet |
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b. at a point farthest away from the
planet |
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c. kinetic energy does not
change |
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14. A satellite moves in an
elliptical orbit around a planet. During its motion, its potential
energy is greatest |
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a. at a point nearest the planet |
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b. potential energy does not
change |
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c. nota |
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In
the next two problems below, a
projectile is fired
horizontally with speed V and from height h above the ground.
No air resistance. |
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15. The
formula for the vertical height is |
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a.
h = gt |
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b.
h = (1/2)*gt2. |
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c.
nota |
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16.
The formula for the horizontal distance
D traveled is |
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a.
D = g*t |
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b.
D = V*t |
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17. What is the
formula for the magnitude F of the attractive force between two point
masses m and M a distance D from each other? |
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18. Two
planets are separated by a distance D and the magnitude of the
force of attraction between them is F. If the distance between the
planets is increased by a factor of 2, the magnitude of the force of
attraction will be |
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a. 4F |
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b. F/4 |
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c. F/8 |
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d. F/16 |