Ch5

1
Chapter 5
2
A Martian lander is approaching the surface. It
is slowing its descent by firing its rocket
motor. Which is the correct free-body diagram for
the lander?
(1) (2) (3) (4) (5)
3
A Martian lander is approaching the surface. It
is slowing its descent by firing its rocket
motor. Which is the correct free-body diagram for
the lander?
(1) (2) (3) (4) (5)
4
An elevator that has descended from the 50th
floor is coming to a halt at the 1st floor. As it
does, your apparent weight is

• 1. More than your true weight.
• 2. Less than your true weight.
• 3. Equal to your true weight.
• 4. Zero.

5
An elevator that has descended from the 50th
floor is coming to a halt at the 1st floor. As it
does, your apparent weight is

• 1. More than your true weight.
• 2. Less than your true weight.
• 3. Equal to your true weight.
• 4. Zero.

6
Rank order, from largest to smallest, the size of
the
to
in these 5 different situations.
friction forces
The box and the floor are made of the same
materials in all situations.
1. fc gt fd gt fe gt fb gt fa. 2. fb gt fc gt fd gt
fe gt fa. 3. fa gt fc fd fe gt fb. 4. fa
fb gt fc fd fe. 5. fb gt fc fd fe gt fa.
7
Rank order, from largest to smallest, the size of
the
to
in these 5 different situations.
friction forces
The box and the floor are made of the same
materials in all situations.
1. fc gt fd gt fe gt fb gt fa. 2. fb gt fc gt fd gt
fe gt fa. 3. fa gt fc fd fe gt fb. 4. fa
fb gt fc fd fe. 5. fb gt fc fd fe gt fa.
8
The terminal speed of a Styrofoam ball is 15 m/s.
Suppose a Styrofoam ball is shot straight down
with an initial speed of 30 m/s. Which velocity
graph is correct?
(1) (2) (3)
(4) (5)
9
The terminal speed of a Styrofoam ball is 15 m/s.
Suppose a Styrofoam ball is shot straight down
with an initial speed of 30 m/s. Which velocity
graph is correct?
(1) (2) (3)
(4) (5)
10
Chapter 5 Reading Quiz
11
The coefficient of static friction is
1. smaller than the coefficient of kinetic
friction. 2. equal to the coefficient of kinetic
friction. 3. larger than the coefficient of
kinetic friction. 4. not discussed in this
chapter.
12
The coefficient of static friction is
1. smaller than the coefficient of kinetic
friction. 2. equal to the coefficient of kinetic
friction. 3. larger than the coefficient of
kinetic friction. 4. not discussed in this
chapter.
13
The force of friction is described by
1. the law of friction. 2. the theory of
friction. 3. a model of friction. 4. the friction
hypothesis.
14
The force of friction is described by
1. the law of friction. 2. the theory of
friction. 3. a model of friction. 4. the friction
hypothesis.