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Long Test 1.3

Motion in 2 Dimensions

CN_______ Name: _____________________________________ Section:_______________ Date: ________

Write the letter of the correct answer on the space before each number. Use CAPITAL letters only. If

answers cannot be found among the choices, supply the correct answer.

For items 1-2, refer to this

1. What is its velocity on the top of its trajectory?A. 25m/s B. 15m/s C. 10m/s D. 0

2. What is its velocity when it returns to where itwas tossed?

A. 25m/s B. 15m/s C. 10m/s D. 03. In a long jump competition, Mike jumps to a

certain height and reached 1meter far. John

jumps to the same height but reaches 0.5meters

away from where he stood. Which of the two

stays in the air longer than the other?

A. MikeB. JohnC. They stayed with the same length of time

4. On the top of a 20m high cliff, Nana fires hiscannon with initial velocity of 10m/s to the

horizontal while at the same time, Nunu fires his

cannon at 20m/s to the horizontal. Which

cannon ball will hit the ground first?A. Nanas cannon ballB. Nunus cannon ballC. All balls hit the ground at the same time

5. Nana throws a stone at 60o directed above theground with initial velocity of 10m/s. If Nanas

location was 12m elevated above the ground.

What is the velocity of the ball just before it hits

the ground?

A. lesser than 10m/s C. equal to 10m/sB. greater than 10m/s

6.

What effect does a reduced gravitational pull onhang time?

A. increase it C. reduce itB. does not change it

7. A cannon ball is fired vertically upward with avelocity of 20m/s. What are its horizontal and

vertical velocities, respectively?

A. 20m/s & 0m/s C. 0m/s & 20m/sB. 15m/s & 15m/s

8. During an experiment, the group found out thatElijahs hang time is 0.40s. If the group

performed the experiment on the moon (with

moon suit), what will happen to Elijahs hang

time? (gmoon=1.67m/s2)

A. greater than 0.40s C. lesser than 0.40sB. equal to 0.40s D. no hangtime

9. A coin is tossed upward and it travels 3.0s toreach its highest peak. How high does it reach?

A. 45m B. 30m C. 20m D. 10m

For items 10-12, refer to this situation.

A cannon ball is fired 60o above the horizontal

with a velocity of 20m/s.

10. What is the horizontal velocity of thecannon ball?

A. 20sin60o C. 20cos60oB. 20tan60o D. 20 sin60o

11. What is the vertical velocity (initial) of thecannon ball?

A. 20sin60o C. 20cos60oB. 20tan60o D. 20 sin60o

12. What is the velocity of the cannon ball onthe top of its trajectory?

A. 20m/s B. 15m/s C. 10m/s D. 0m/s13. A plane that is flying at 500m above at an

average speed of 150m/s drops a water

bomb to the target on the ground. How far,

horizontally should the bomb be released to

hit the target?A. 500m B. 650m C. 1000m D. 1500m

For items 14-15, refer to this situation.

Daring Phoebe wanted to exhibit an

extraordinary stunt by ejecting herself directly

upward from a horizontally running car at

constant velocity.

14. Relative to the car, where will DaringPhoebe land if after she ejects herself, the car

stopped?

A. behind the carB. on the carC. in front of the car

15. Relative to the car, where will DaringPhoebe land if after she ejects herself, the car

continues to run?

A. behind the carB. on the carC. in front of the car

16. A 1-kg cannon ball was fired from cannon tothe direction 45o from the horizontal.

Suppose a cannon ball of twice the mass wasfired at the same initial velocity and at the

same direction, how far away will it reach

compared to the 1-kg cannon ball?

A. twice as farB. same distanceC. half as far

A ball is tossed directly upward with an initial

velocity of 25m/s.

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17. Chloe throws a stone to the direction 30obelow the horizontal with a speed of 20m/s,

what is its vertical speed after 1s?

A. 30m/s B.20m/s C. 10m/s D. 0m/s18. Chloe throws a stone to the direction 30o

above the horizontal with a speed of 20m/s,

what is its vertical speed after 1s?

A. 30m/s B.20m/s C. 10m/s D. 0m/s19. Suppose a small stone is fired at 50o with the

horizontal with an initial velocity of 50m/s.

How fast is it moving on top of its

trajectory?

A. 38m/s B. 32 m/s C. 10 m/s D. 0 m/s20. (Refer to the problem in number 19) What is its

horizontal velocity?

A. 38m/s B. 32 m/s C. 10 m/s D. 0 m/s21. (Refer to the problem in number 16) What is its

vertical velocity?

A. 38m/s B. 32 m/s C. 10 m/s D. 0 m/sFor items 21-24, refer to this situation.

22. What is the initial speed of the girls ballrelative to the boy?

A. 1.0 m/s C. 2.0 m/sB. 1.5 m/s D. 3.0 m/s

23. If air resistance is disregarded, which ballwill hit the ground first?

A. the boys ballB. the girls ballC. neitherD. cannot be determined

24. If air resistance is disregarded, which ballwill have a greater speed (relative to the

ground) when it hits the ground?

A. the boys ball C. neitherB. the girls ball D. cannot be determined25. What is the speed of the girls ball when it

hits the ground?

A. 1.0 m/s C. 6.2 m/sB. 3.0 m/s D. 8.4 m/s

26. A football is kicked at an angle withrespect to the horizontal. During this event,

the acceleration of the football is

A. 10 m/s2 at all times.B. zero when it has reached the highest

point in its trajectory.

C. positive as it rises and negative as itfalls.

D. 10 m/s2 at the start and drops to someconstant lower value as it approaches

the ground.

27. A cannonball is fired horizontally at 10 m/sfrom a cliff. Its speed one second after beingfired is aboutA. 10 m/s. C. 16 m/s.B. 14 m/s. D. 20 m/s.

28. A baseball is hit upward and travels along aparabolic arc before it strikes the ground.Which one of the following statements is

necessarily true?

A. The acceleration of the ball decreases asthe ball moves upward.

B. The velocity of the ball is zero when theball is at the highest point in the arc.

C. The acceleration of the ball is 0 m/s2when the ball is at the highest point in

the arc.

D. The x-component of the velocity of theball is the same throughout the ball's

flight.

29. How do the x- andy- components of thevelocity vector of the ball compare at the

points Band C?

A. The x- andy- are non-zero at B but zeroat C

B. The x- never changed; they- at C is 0m/s.

C. The x- andy- components are larger at BD. They- is upward at B, downward at C

30. Which statement is true concerning the ballwhen it is at C, the highest point in its

trajectory? The balls

A. velocity and acceleration are both zero.B. velocity is perpendicular to its

acceleration.

C. velocity is not zero, but its accelerationis zero.

D. velocity is zero, but its acceleration isnot zero.

A girl riding a bicycle at 2.0 m/s throws a tennis

ball horizontally forward at a speed of 1.0 m/s

from a height of 1.5 m. At the same moment, a

boy standing on the sidewalk drops a tennis ball

straight down from a height of 1.5 m.

A tennis ball is thrown upward at an angle from

pointA. It follows a parabolic trajectory and hits

the ground at point D. At the instant shown, the

ball is at point B. Point C represents the highest

position of the ball above the ground.

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BONUS:

A golf ball with an initial angle of 43 lands exactly

240 m down the range on a level course. At what

initial speed did it start moving?

2

1 0 2 40

2 43

2400

86

49

sin

( )( )sin ( )

sin

gR

i

ms

v

A golf ball with an initial angle of 34 lands exactly

240 m down the range on a level course. At what

initial speed did it start moving?

2

1 0 2 40

2 34

2400

68

50 88 51

sin

( )( )

sin ( )

sin

.

gR

i

m ms s

v