72532046-IB-Questions-on-Projectile-Motion.doc

IB questions on Topic 9.1_Projectile Motion

1.

The diagram below shows the path of a projectile in the absence of air resistance. Vertical  p o s i t i o n

H o r iz o n ta l p o s itio n

Which one of the following diagrams best represents the path of the projectile under the same initial conditions when the air resistance is taken into account? (The path in absence of air resistance is shown for comparison as a dotted line.) A .

B .

Vertical  p o s i t i o n

Vertical  p o s i t i o n

H o riz o n ta l p o s itio n  .

H o riz o n ta l p o s itio n ! .

Vertical  p o s i t i o n

Vertical  p o s i t i o n

H o riz o n ta l p o s itio n

H o riz o n ta l p o s itio n (1)

2.

Which one of the following is a true statement concerning the "ertical component of the "elocit# and the acceleration of a projectile when it is at it s ma$imum height? (The acceleration of free fall is g.) Vertical component of veloc locit

!cceleration

A.

ma$imum

zero

B.

ma$imum

 g 

.

zero

zero

!.

zero

 g  (1)

1

".

A stone is thrown at an angle to the horizontal. %gnoring air resis tance& the horizontal component of the initial "elocit# of the stone determines the "alue of  A.

range onl#.

B.

ma$imum height onl#.

.

range and ma$imum height.

!.

range and time of flight. (1)

#.

A ball is thrown horizontall# from the top of a cliff. Air resistance is negligible. Which of the following diagrams best represents the subse'uent path of the ball? A .

B .

 .

! .

(1)

2 

$.

A stone is projected horizontall# from the top of a cliff. (eglecting air resistance& which one of the following correctl# describes what happens to the horizontal component of "elocit# and to the "ertical component of "elocit#? %ori&ontal component of velocit

Vertical component of velocit

A.

!ecreases

%ncreases

B.

!ecreases

onstant

.

onstant

onstant

!.

onstant

%ncreases (1)

'.

Two identical metal spheres ) and * are released at the s ame time from the same height abo"e the horizontal ground. +phere ) falls "erticall# from rest. +phere * is projected horizontall# as shown below. )

*

ground Air resistance is negligible. Which of the following statements is correct? A.

+phere ) hits the ground before sphere * because it tra"els a shorter distance.

B.

+phere * hits the ground before sphere ) because its initial "elocit# is greater.

.

The spheres hit the ground at the same time because horizontal motion does not affect "ertical motion.

!.

The spheres hit the ground at the same time because the# ha"e e'ual weights. (1)

3

.

The diagram below shows the trajector# of a ball thrown into the air. There is no air resistance. t ra j e c t o r # o f b a l l

) A

B  !

Which arrow gi"es the direction of the resultant force on the ball at the point )? A.

A

B.

B

.



!.

! (1)

4

9.

A stone is thrown from the top of a cliff with speed v at an angle θ  abo"e the horizontal& as shown.

cliff 

Air resistance is negligible and the acceleration of free fall is  g . What is the horizontal "elocit# of the stone a time t  after the stone has been thrown? A.

v sinθ 

B.

v sinθ  , gt 

.

v cosθ 

!.

v cosθ  , gt  (1)

1.

A particle is projected horizontall# with speed v from a height H . %t lands a horizontal distance  R from the point of launch as shown in the diagram below. v

 H 

 R A second particle is projected horizontall# from the same height with speed - v. (eglecting air resistance the horizontal distance tra"elled b# this particle is A. B.

 R. - R.

.

- R.

!.

 R. (1)

5 

11.

This 'uestion is about projectile motion. A small steel ball is projected horizontall# from the edge of a bench. /lash photographs of the  ball are taken at 0.10 s inter"als. The resulting images are shown against a scale as in the diagram below. d i s ta n c e 4 c m 0 -0 0 20 30 100 0

-0

0

20 d i s ta n c e 4 c m 30

100

1-0

10  5a6

7se the diagram to determine 5i6

the constant horizontal speed of the ball. ........................................................................................................................... ........................................................................................................................... ........................................................................................................................... (2)

 5ii6

the acceleration of free fall. ........................................................................................................................... ........................................................................................................................... ........................................................................................................................... (2) 6 

 5b6

8ark on the diagram the position of the ball 0.90 s after projection. %n the space below& #ou should carr# out an# calculations so that #ou can accuratel#  position the ball. ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... (")

5c6

A second ball is projected from the bench at the same speed as the original ball. The ball has small mass so that air resistance cannot be neglected. !raw on the diagram the appro$imate shape of the path #ou would e$pect the ball to take. (") (Total 1 mar*s)

12.

This 'uestion is about projectile motion. A stone of mass 0. kg is thrown horizontall# from the top of a cliff with a speed of -- m s shown below.

 ,1

 as

- - m s  , 1

:- m

cliff 

s e a le " e l The cliff is :- m high. 5a6

alculate the total kinetic energ# of the stone at sea le"el assuming air resistance is negligible. ................................................................................................................................... ................................................................................................................................... ................................................................................................................................... ................................................................................................................................... (")

7 

5b6

%n practice& air resistance is not negligible. !uring the motion of the stone from the top of the cliff to sea le"el& : % of the total energ# of the stone is transferred due to air resistance. !etermine the speed at which the stone reaches sea le"el. ................................................................................................................................... ................................................................................................................................... ................................................................................................................................... (2) (Total $ mar*s)

1".

This 'uestion is about trajector# motion. Antonia stands at the edge of a "ertical cliff and throws a stone upwards at an angle of 20; to the horizontal. v = 3 .0 m s

 , 1

20;

+ea

 ,1

The stone lea"es Antonia