Download - Physics Homework 5
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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.