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Unformatted text preview: \r AN gel LEW Kev! College Physics I  PHY 2053
Test II  May 27, 2010 — FORM A Put answers on Scantron. Clearly indicate which test (A or B) you were using.
Only return the Scantron, keep the test FORMULAS.
Weight: w = mg, Acceleration of gravity: g 2 9.80 111/82. TWO—dimensional projectile motion:
a: = $0 + voﬂt. y : yo + unﬁt —1/29t2. “Um 2 now. g Dy 2 110,1, ~ gt. Components of the velocity:
vx : Unease.
vy = voysmél. Newton’s second law: 2F 2 ma. Newton’s law of universal gravitation:
F : Gm—ﬂﬂ, Where: G = 6.67 x 10—11 N1112/kg2. Maximum static frictional force: fs’mm : usF N.
Kinetic frictional force: fk 2 ukFN.
2 Centripetal acceleration: ac : A person releases two stones from the top of a cliﬁ: overlooking a lake. The
stones have the same mass. Stone 1 is dropped straight down, stone 2 is thrown
with an initial horizontal velocity of 20 m/s. Neglect air resistance. Questions
1~7 refer to this situation. 1. Which stone strikes the water with the greatest speed?
a, Stone 1; @ﬁtone 2; 0. They strike with the same speed. 2. Which stone strikes the water ﬁrst? a. Stone 1;
10. Stone 2; @hey strike at the same time. gang, t“ 3. Which stone has the greater vertical component to its velocity (Dy) at the
moment of impact? M a. Stone 1;
b. Stone 2; @hey have the same ﬂy at the moment of impact. 4. Which stone has the greater horizontal component to its velocity (11$) at the
moment of impact? a. Stone 1; 3 @Stone 2; c. They have the same ’Um at the moment of impact. 5. Which stone has traveled the greater distance when it strikes the water?
a. Stone 1; Stone 2; C. They have traveled the same distance. 6. If the initial speed of stone 2 were doubled, the time for it to strike the water
would: ‘ a. increase; & WA 3 I». . VQ} K5 kt Jr
C b. decrease; uw dig/(U
@remain the same. Q 7. If the mass of stone 2 were doubled, the time for it to strike the water would:
a. increase; b. decrease;
©emain the same. In a famous experiment Galileo is rumored to have dropped two unequal weights
simultaneously from the top of the leaning tower of Pisa. Assume air resistance
to be negligible. Questions 811 refer to this situation. 8. Which object has the greater force acting on it after it has been released?
@The heavier object.
A b. The ligher objeect.
c. The are the same. \
. 5 a
.m, .J) 9. 'Which‘object has the greater acceleration after it has been released?
a. The heavier object.
b. The ligher objeect. @The accelerations are the same. 10. Which object has the greater impact speed?
a. The heavier object. : b. The ligher objeect.
@}The impact speeds are the same. 11. Which object strikes the ground ﬁrst?
a. The heavier object. b. The ligher object.
@‘ﬂ‘he objects strike at the same time. A golfer hits a ball from the origin with an initial speed of 50.0 m/s at an angle
of 33.00 above the horizontal. The ball is moving down when it lands on a green
that is 4.00 m above the level where the ball was struck. Neglect air resistance.
Questions 1214 refer to this situation. 761:0 \lco; [ital/d3
12. How long is the ball in the air? W A ,1 I , .
a. less than 4.0 sec; k3“ /\) \i ‘3 " : .XTZ' 52 (“(3
@between 4.0 and 8.0 sec.; ’ ? f] ~ i
E c. between 8.0 and 12 see; ; P a 1 (5 mi i\ Kl
d. more than 12 sec. ’ a ”‘ _ 13. How far has the ball traveled in the horizontal direction when it lands?
a. less than 50 m.; b. between 50 and 100111.; a gag T \{Q FR V : M
0. between 100 and 200 m.; ’ '
11’)” @more than 200 m.
14. What is the speed of the ball 3.8 seconds after it has been hit?
a. less than 20 m/s; k  (m 1 t 3
. » L“ 4,
b. between 20 and 30 m/s; V9 K 3 L1 l ’ I, u I,
9. between 30 and 40 m/s; I . 6T? ( _ wl Q l :5
b 1 4 Va : .274!“ v
/ wiiore t ran 0 m/s. . \l 3 \f( i7 r6 \ L
A skydiver jumps out of an airplane. The skydiver’s weight is 800 N. Skydivers ‘ .
would not survive long if there were no air resistance, so this time we do not ig 4: D M (x
nore air resistance. As the diver is falling her speed increases and consequently the air resistance also increases. Air resistance, just like friction, acts in the
direction opposite to the motion. Questions 1518 refer to this situation. 15. After she has been falling for a while the air resistance on the skydiver is
600 N. The net force on the skydiver at that time is: 200 N;
b. 600 N; IQ? c. 800 N;
d. 1400 N. A .‘:> its 16. At some point the air resistance on the skydiver will become 800 N. At that
point the skydiver’s acceleration is:
QtyO m/s ;
b. not zero but less than g;
0. equal to g;
d. greater than g. 17. When the skydiver opens her parachute the air resistance increases to 1400
N. At that point her acceleration is:
Al 0“ if” a. upward, equal to g; 3’. $6
Q} a, f M ;. /\/ @upward, but less than g; b
c. downward, equal to g;
d. downward, less than g. 18. After she opens her parachute, the skydiver reaches a constant terminal
yelocity. At that point the net force on her is: x" :
@ﬁero;
b. not zero; pointing upward;
c. not zero, pointing downward;
d. cannot be determined from the given information. 19. A 10 N book is resting on a table. The upwards force on the book is equal
to 10 N because of: @Newton’s ﬁrst law;
b. Newton’s second law;
c. Newton’s third law; 20. The book and table in Question 20 are now given amUpwards/aicceleration
of 2 m/s2. The upwards force on the book Will: R” W
a. remain equal to 10 N;
@be larger than 10 N;
c, be less than 10 N. 21. You are inside an elevator that is moving down at a constant velocity of
9.8 m/s. Your apparent weight is: a. zero;
b. more than your actual weight;
c. less than your actual weight but not zero;
Z‘dfyequal to your actual weight. A 20 kg mass on the left is connected by a rope to a 30 kg mass on the right.
Both masses are on a horizontal surface. The rightmost mass is pulled with a horizontal force of 400 N. Friction is negligible. Questions 2224 refer to this
situation. 22. The acceleration of the system is:
a. less than 4.5 m/sz;
@etween 4.5 111/52 and 90 111/82; mm”, g c. between 9.0 iii/s2 and 13 iii/s2; M ‘
/ 01. greater than 13 iii/s2. 23. The tension in the rope joining the two masses equals:
a.“zero;
(ii/bot zero, but less than 200 N;
c. between 200 and 400 N;
d. equal to 400 N. 24. The system will move: ‘ a. with constant velocity;
C b. with decreasing velocity;
'Qwith mcreasmg velocrty. 25. Two cars of different masses moving at the same speed undergo a head—on
collision. Which car exerts the larger impact force?
a. the heavier car;
b. the lighter car;
@the forces are equal;
d. cannot be determined. 26. Two cars of the same mass but traveling at different speeds undergo a head—
on collision. Which car exerts the larger impact force?
a. the faster moving car;
b. the slower moving car;
(IE/Tithe forces are equal;
d. cannot be determined. 27. The units of the static friction coefﬁcient are:
a. N; b. iii/s2; c. kg; é: @110 units. 28. What happens to the gravitational force between two masses if the distance
between them is doubled? The force is multiplied by: 331/4; . 1/2; 3.31;. (m ‘M “L % C C 29. Consider the acceleration of gravity ’g’ and the constant ‘G’ in Newton’s
law of universal gravitation. When you travel from Earth to Mars, which one(s)
change(s)?
a. both remain the same; (“ng changes, G remains the same;
0. G changes, g remains the same; (:1. both change.
30. What happens to the centripetal acceleration of an object that is undergo— ing uniform circular motion if the speed of the object is doubled and the mass is
doubled, all other quantities remaining the same? The centripetal acceleration: a. stays the same; a)
r 9\
6L ; \l / r, b. doubles;
@quadruples;
d. becomes eight times as large as before.
31. When a car moves around an unbanked curve, the force that allows it to
make the turn is:
a. weight; b. normal force; @tatic friction; d. kinetic friction. 32. The orbital speed needed to keep a satellite in orbit a distance 7‘ from the
center of the Earth, does not depend on: a. the radius of the orbit; b. the universal gravitational constant, G; c. the mass of the Earth; d. the mass of the satellite. A child rides on a toboggan that is being pulled<up/a hill inclined at an angle of
25.00 with respect to the horizontal. The coefﬁcient of kinetic friction between
the toboggan and the hill is 0.42. The tension in the rope that is used to pull the
toboggan is 800 N. The combined mass of the child and the toboggan is 90.0 kg
and they are to be treated as one system. Questions 33—34 refer to this situation. 33. How many forces are acting on the system? 4/
a. Two; /h. Three; Kg 7 Four; I. w
d. Five. "\ f — f
\.,_g\\ u f 34. The magnitude of the acceleration of the system is:
@less than 3 111/52;
b. between 3 and 6 111/82;
A c. between 6 and 9 111/82;
d. more than 9 111/82. 35. A 1250kg car travels at a speed of 20 iii/s on a circle of radius 30 in on a
frictionless banked road. At what angle must the road be banked for the car to
stay on the road? a. less than 300; > ’ between 300 and 450;;
’é.\between 450 and 60 0;
Cd/more than 60 0. 36. In the previous question, what will happen to the banking angle if the car’s A mass increases? The banking angle:
a. increases;
b. decreases;
@‘emains the same. ...
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This note was uploaded on 02/02/2012 for the course PHY 2053 taught by Professor N/a during the Spring '10 term at FAU.
 Spring '10
 n/a
 Physics

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