Transcript Knight_ch04

Chapter 4
Two forces are exerted on an object.
What third force would make the
net force point to the left?
(1)
(2)
(3)
(4)
Two forces are exerted on an object.
What third force would make the
net force point to the left?
(1)
(2)
(3)
(4)
You’ve just kicked a rock, and it is now sliding across
the ground about 2 meters in front of you. Which of
these forces act on the ball?
1) Gravity, acting downward.
2) The normal force, acting upward.
3) The force of the kick, acting in the direction of
motion.
4) Friction, acting opposite the direction of motion.
5) 1, 2 and 4 but not 3.
You’ve just kicked a rock, and it is now sliding across
the ground about 2 meters in front of you. Which of
these forces act on the ball?
1) Gravity, acting downward.
2) The normal force, acting upward.
3) The force of the kick, acting in the direction of
motion.
4) Friction, acting opposite the direction of motion.
5) 1, 2 and 4 but not 3.
Two rubber bands stretched the standard distance cause an
object to accelerate at 2 m/s2. Suppose another object with
twice the mass is pulled by four rubber bands stretched the
standard length. The acceleration of this second object is
1) 1 m/s2 .
2) 2 m/s2 .
3) 4 m/s2 .
4) 8 m/s2 .
5) 16 m/s2 .
Two rubber bands stretched the standard distance cause an
object to accelerate at 2 m/s2. Suppose another object with
twice the mass is pulled by four rubber bands stretched the
standard length. The acceleration of this second object is
1) 1 m/s2 .
2) 2 m/s2 .
3) 4 m/s2 .
4) 8 m/s2 .
5) 16 m/s2 .
Three forces act on an object. In which direction does the
object accelerate?
(1)
(2)
(3)
(4)
(5)
Three forces act on an object. In which direction does the
object accelerate?
(1)
(2)
(3)
(4)
(5)
An elevator suspended by a cable is moving upward and
slowing to a stop. Which free-body diagram is correct?
(1)
(2)
(3)
(4)
(5)
An elevator suspended by a cable is moving upward and
slowing to a stop. Which free-body diagram is correct?
(1)
(2)
(3)
(4)
(5)
Chapter 4
Reading Quiz
What is a “net force?”
1) The weight excluding the container
2) The vector sum of all forces in a problem
3) The vector sum of all forces acting on an object
4) The vector force applied by a net
5) The vector sum of all forces that add up to zero
What is a “net force?”
1) The weight excluding the container
2) The vector sum of all forces in a problem
3) The vector sum of all forces acting on an object
4) The vector force applied by a net
5) The vector sum of all forces that add up to zero
Which of the following are steps used to identify the
forces acting on an object?
1) Draw a closed curve around the system
2) Identify “the system” and “the environment”
3) Draw a picture of the situation
4) All of the above
5) None of the above
Which of the following are steps used to identify the
forces acting on an object?
1) Draw a closed curve around the system
2) Identify “the system” and “the environment”
3) Draw a picture of the situation
4) All of the above
5) None of the above
Which of these is not a force discussed in this chapter?
1)The tension force
2)The orthogonal force
3)The normal force
4)The thrust force
5)None of the above
Which of these is not a force discussed in this chapter?
1)The tension force
2)The orthogonal force
3)The normal force
4)The thrust force
5)None of the above
Newton’s third law
1)is another name for the law of inertia.
2)says that the velocity of an object is determined by
the net force on the object.
3)says that every action has an equal and opposite
reaction.
4)was not discussed in this chapter.
Newton’s third law
1)is another name for the law of inertia.
2)says that the velocity of an object is determined by
the net force on the object.
3)says that every action has an equal and opposite
reaction.
4)was not discussed in this chapter.