__SAMPLE EXAM FOR 2-Dimensional motion
and Newton’s Laws of Motion (CH's 3,4)__

1] Let East represent the positive x
axis and North
the positive y axis. A constant wind with a speed of 10.0 km/hr is
blowing due
NE. You have a model airplane that flies at 30.0 km/hr in level flight
in still
air. You start its engine and release it in the direction due NW. What
will be
the displacement of the airplane relative to your position after it
flies for
10.0 minutes?

ANSW: 5.26 km @ 117 degrees

2] Assume the motion of a kicked football follows that of a
projectile above
the surface of the earth. The ball is kicked from directly in
front of
the goalpost and hits the crossbar. If the ball was kicked from 20.0 m
away
with a velocity of 15.0 m/s at an angle of 45 degrees to the
horizontal, what
is the height of the crossbar?

ANSW: 2.53 m

3] A block of mass 2.0 kg is observed to slide down an incline at a
constant
velocity when the incline makes an angle of 30 degrees with the
horizontal.
What is the coefficient of kinetic friction between the block and
incline?

ANSW: 0.58

3B] EXPLAIN
BRIEFLY **which one** of __Credit
will be given only if an explanation is included!} __NOTE: All 3
laws can be
applied here but ONE will best describe the state of this object.

4] A mass of 0.50 kg is hanging vertically by a string. It is
known that
the string will break if the tension in it exceeds 25 N. What is the
maximum
acceleration that can be given to the mass by pulling up on the string?

ANSW: 40 m/s/s

Describe the condition(s) that would be required for the tension in
the
string to be equal to zero.

**1] **A plane is flying directly over ETSU at the moment
you begin
this exam. The pilot is heading due West at 500 km/hr, but he is flying
in a 60
km/hr wind that is blowing due South. Where will the plane be (with
respect to
ETSU) when the exam period is over 80 minutes from
now.

ANSW: 672 km @ 6.8 degrees SW

**2]** Assume the flight of a baseball follows that of a
projectile above
the surface of the Earth. You are the batter and hit a low pitched
baseball
that lands at the top of an outfield wall 85.0 meters away. If you gave
the
baseball a velocity of 30.0 m/s at an angle of 40.0 degrees to the
horizontal,
what is the velocity of the ball when it strikes the top of the wall? (__ignore____ the initial height of the ball
when you hit
it__)

ANSW: 28.6 m/s @ 36.5 degrees below
horizontal

**4] **You watch the following events happen while standing on
the shore.
Two sailing ships are passing your location. As you watch ship #1 pass
by,
moving at constant velocity, a stone is dropped from a tall mast of the
ship
and lands on its deck. Ship #2 passes by, moving with a constant
acceleration,
and a stone is also dropped from a tall mast landing on its deck.
EXPLAIN, with
reference to the appropriate laws of motion, where each stone (#1 and
#2) lands
relative to the mast from which it fell. {i.e., do they land at the
foot of the
mast or behind it?}

**5]** You are pulling a small child on a snow sled up a slope
that makes
a 30 degree angle with the horizontal . The
combined
mass of the child and sled is 20.0 kg. It is known that the coefficient
of
kinetic friction between the snow and sled is m
_{k} = 0.130 . If you pull the rope
such that
a constant force of 125 N is acting on the sled parallel to the surface
of the
slope, what is the acceleration of the sled/child combination **up**
the
incline?

ANSW: +.245 m/s/s

SAMPLE MULTIPLE CHOICE QUESTIONS FOR MOTION AND NEWTON'S LAWS

1) A packing crate slides down an inclined ramp at constant velocity. Thus, we can deduce that

a) a frictional force is acting on it.

b) a net downward force is acting on it.

c) it may be accelerating.

d) it is not acted on by an appreciable gravitational force.

2) When you sit in a chair, the sum of all the forces acting on you while you sit

a) is up

b) is down

c) depends on your weight

d) is zero

3) If you blow up a balloon and then release it, the balloon will fly away. This is an illustration of

a) Newton's 1st law

b) Newton's 2nd law

c) Newton's 3rd law

d) the law of gravity

4) A mass is suspended from the ceiling by means of a string. The Earth pulls downward on the mass with the weight force

of the mass equal to 8 N. If this is the "action" force of the 3rd law, what is the "reaction" force?

a) the string pulling upward on the mass with an 8 N force

b) the ceiling pulling upward on the string with an 8 N force

c) the string pulling downward on the ceiling with an 8 N force

d) the mass pulling upward on the Earth with an 8 N force

5) A stone is thrown horizontally from the top of a tower at the same instant another stone is dropped vertically. Which stone is traveling with the greater speed when it hits the level ground below?

a) the dropped stone

b) the thrown stone

c) their speeds are the same since they will hit the ground at the same time

d) it is impossible to determine an answer from the information given

6) If the acceleration of an object is always directed perpendicular to its velocity,

a) then the object is speeding up

b) then the object is slowing down

c) the the object is changing its direction of motion

d) then the velocity remains constant

ANSWERS

1) a

2) d

3) c

4) d

5) b

6) c