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Physics 101/Spring Due Thu, Feb 27 th Name ____________________________________ Section __________

Fill in the blank. (25 points)

1. The horizontal component of the velocity of a projectile in free fall is (constant / accelerating) ________and the vertical component is (constant / accelerating) _________ .

2. The horizontal distance a ball travels down the field is called the ____________________ .3. The vertical component of the velocity determines what two issues regarding a projectile in free flight?

Distance __________________________

Time _____________________________

4. Fill in the blank with 1/25, 1/5, same, 5 times, 25 times. Two balls are kicked off the ground so Ball Bshorizontal component is 5 times greater than Ball As, andBall Bs vertical component is the same as As.

Ball Bs maximum height is ____________ Ball As.

Ball B is in the air for a time that is ________________ the time that ball A is in the air.

Ball Bs range is _____________ Ball As range.

5. Fill in the blank with greater than, less than, or the same as. Two balls A and B leave the ground with thesame initial speed.

Ball A is kicked at 30 and ball B is kicked at 60.

The range of A is _______________ the range of B.

The height A is ___________ as the height of B.

The time A is in the air is ___________ the time B is in the air.

Ball A is kicked at 60 and ball B is kicked at 45.

The range of A is _______________ the range of B.

The height A is ___________ as the height of B.

The time A is in the air is ___________ the time B is in the air.

Ball A is kicked at 20 and ball B is kicked at 55.

The range of A is _______________ the range of B.

The height A is ___________ as the height of B.

6. When ball A is kicked in the air, if there is no gravity the ball will have a straight line trajectory (see fig. above). Ifthere is gravity, neglecting air resistance, how far below the straight line trajectory, in meters will the ball be, 5

seconds into flight (hint: d = g t2) _________________________________?

7. According to the Universal Law of Gravitation, between any two masses A and B there is anforce (see ppt lecture for Ch 9, Law of Universal Gravitation slide).

This force (increases / decreases) ______________________________ with increasing mass of the objectsand (increases / decreases) _____________________________ with increasing AB separation distance.

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A B

8. The force of the Earth acting on the Sun and the force of the Sun acting on the Earth are the same because they are

an ___________________________ ___________________________________pair.

9. A law regarding force, with distance squared in the denominator is an _____________ ______________ law.

10. Planets A and B orbit a star. A and B have the same mass but B is four times farther from the star than A.

The force of the star on A is (how many times) the force of the star on B?

11. Planets A and B orbit a star. Planet A has 5 times the mass of planet B andthe star has 300 times the mass of planet A. The force of the star on planet A is

(greater than / less than / equal to) the force of planet A on the

star. The force of the star on planet A is ___________________(how many?) times the

force of the star on planet B.

12. Mr. Face weighs 400 N on the surface of PlanetA (below). How much does Mr. Face weigh on each planet

below? (B and C, 2 points each; D, 3 points)

13. If Mr. Face did actually weigh 400 N on Planet A, and if Planet A had the same gravitational force as the

Earth, what would Mr. Faces massbe on Planet A? (hint: Fg= mg) ______________________________

14. What would Mr. Faces mass be on planet B? ________________________________________________

B C DA

400 lb

Planet Bhas four times

the mass and the same

size asA.

Planet Chas a quarter the

radius and the same mass

asA.

Planet Dhas twice the

radius and four times

the mass ofA.