SMDEP Physics

1
SMDEP Physics

• Projectile motion

2
Ch. 3, 28

• 1/6 as far
• 6 times as far
• 36 times as far
• 3.4 times as far
• Other
• Didnt finish

3
Ch. 3, 32

• 12.9m
• 129m
• 1.29m
• 38.7m
• Other
• Didnt finish

4
Ch. 3, 37

• 32.7 s
• 3.27 s
• 5.71 s
• 0 s
• Other
• Didnt finish

5
Attendance Whats your favorite type of music?

1. Jazz
2. Classical
3. Hip-hop
4. Rock
5. Techno
6. Country
7. American Idol

6
Survey How much time are you spending on reading
plus homework each day?

1. 0-1 hour
2. 1-2 hours
3. 2-3 hours
4. 3-4 hours
5. 4-5 hours
6. More than 5 hours

7
The following graph shows position as a function
of time for two trains running on parallel
tracks. Which of the following is true?

1. At time T both trains have the same velocity
2. Both trains speed up all the time
3. Both trains have the same velocity at some time
   before T
4. Somewhere on the graph, both trains have the same
   acceleration

8
Train 1
position
Train 2
T
time
9
The following graph shows position as a function
of time for two trains running on parallel
tracks. Which of the following is true?

1. At time T both trains have the same velocity
2. Both trains speed up all the time
3. Both trains have the same velocity at some time
   before T
4. Somewhere on the graph, both trains have the same
   acceleration

10
For the same graph, compare the trains average
velocities during the time interval between t0
and tT

1. ltv1gt greater than ltv2gt
2. ltv1gt less than ltv2gt
3. ltv1gt equal to ltv2gt

11
Train 1
position
Train 2
T
time
12
For the same graph, compare the trains average
velocities during the time interval between t0
and tT

1. ltv1gt greater than ltv2gt
2. ltv1gt less than ltv2gt
3. ltv1gt equal to ltv2gt

13
The following graph shows the velocity of three
objects during the time interval from t1 to t2.
All three have the same initial and final
velocities. Which object has the greatest
velocity over the entire interval?

1. 1
2. 2
3. 3
4. All three have the same average velocity.
5. Cannot tell without knowing the starting
   positions.

14
velocity
1
2
3
t2
t1
time
15
The following graph shows the velocity of three
objects during the time interval from t1 to t2.
All three have the same initial and final
velocities. Which object has the greatest
velocity over the entire interval?

1. 1
2. 2
3. 3
4. All three have the same average velocity.
5. Cannot tell without knowing the starting
   positions.

16
A stone is launched vertically up, and its speed
slows under the influence of gravity. Suppose we
film this motion and play the tape backward (so
the tape begins with the ball at a high point and
ends with the ball at a low point).

• What you see on the tape could never happen in
  reality
• The tape shows the motion of a stone in free fall
  but the acceleration is upward rather than
  downward.
• The tape shows the motion of a stone in free fall
  with downward acceleration g.

17
A ball is dropped from a cliff (from rest). A
second ball is thrown upward from the cliff, and
eventually falls back to where the first ball
hit.

• Both balls have the same speed when they pass the
  cliff.
• Both balls hit the ground below with the same
  velocity.
• Both balls have the same acceleration.
• Both balls take the same time to fall starting
  from when they pass the cliff.

18
A person standing at the edge of a cliff throws
one ball straight up and another straight down at
the same initial speed. Neglecting air
resistance, which ball hits the ground with
greater speed?

1. The one thrown upward.
2. The one thrown downward.
3. Neither they hit with the same speed.
4. Not enough information to tell.

19
A bowling ball is dropped from a building at the
same time that a stone is launched upward from
the ground. The initial speed of the stone is
equal to the speed of the ball just before it
hits the ground. The ball and stone cross

1. Above
2. Exactly at
3. Below

..half the height of the building.
20
An astronaut stands on the moon where the local
acceleration due to gravity, gMoon is 1/6 the
value on Earth, gEarth 9.8 m/s2. If the
astronaut drops a golf ball from a certain
height, the time it takes to hit the ground

1. Is greater than
2. Is equal to
3. Is less than

the time it takes a golf ball on Earth to fall
the same distance.
21
Consider the following displacement r 6t i
4 j ? 10 t2 kIn what direction is the
acceleration?

1. k
2. - k
3. In the direction of the vector 6i?20k
4. Cant tell without a lot of algebra
5. Cant say without specifying the time

22
Consider the following four situations1. You
make a U-turn at constant speed2. You drive
forward, stop, then go in reverse3. You make a
right turn at constant speed4. You make a right
turn and brake while turningFor which of these
situations do you experience nonzero average
acceleration?

1. 4
2. 2 and 4
3. 2
4. 1,2, and 4
5. All of them

23
Q. Two velocities with magnitudes 3.0 m/s and 4.0
m/s are added. Which of the following could NOT
be the magnitude of their resultant velocity?

• 3.5 m/s
• 5.0 m/s
• 6.6 m/s
• 7.3 m/s

24
What is the minimum number of forces of equal
magnitude that, when added, yield a vector sum of
zero?

1. Five
2. Four
3. Three
4. Two
5. One

25
What is the minimum number of forces of unequal
magnitude that, when added, yield a vector sum of
zero?

1. Five
2. Four
3. Three
4. Two
5. One

26
Two penguins are sliding on adjacent paths along
the horizontal surface of an iceberg. One moves
twice as fast as the other, and they both pass
over the edge at the same instant. Which penguin
hits the water first?

1. The penguin with the faster initial horizontal
   velocity.
2. The slower penguin.
3. They hit the water at the same time.

27
Where do the penguins land relative to each other?

• They land in nearly the same spot because the
  initial velocity on the iceberg doesnt affect
  the subsequent motion.
• The faster penguin travels further from the
  iceberg.
• The slower penguin travels further from the
  iceberg because it takes longer to fall.