Homework Assignment 6:
Due beginning of class
Name:
Show all work for complete credit.
• Unless specified otherwise, round your answers to a reasonable number of
significant figures. (Rules are given in chapter 1 or round to 2-3 figures.)
• Give very large or very small values in scientific notation.
You will need to reference the following documents:
• Homework Guide: Energy
#1a. Chapter 6: Problem #45 (Underline or highlight the question.)
A 0.50-kg object is at rest at the origin of a coordinate system. A 3.0-N force in the +x-direction acts on
the object for 1.50 s. (a) What is the velocity at the end of this interval? (b) At the end of the interval, a
constant force of 4.0 N is applied in the –x-direction for 3.0 s. What is the velocity at the end of the 3.0 s?
Plan: Do the problem as you would have from chapters 2 and 4. Start with a Motion
Diagram and a Free-Body Diagram. Write all the equations and solve.
Show your work:
Answer the question: Be sure to include units.
Evaluate:
Do a unit analysis (if you didn’t do one above).
Is the magnitude of the answer reasonable? Give a reason.
Phy 101: HW6: Fall07
Eyres
Homework Assignment 6:
Due beginning of class
Name:
#1b. Chapter 6: Problem #45 (Underline or highlight the question.)
A 0.50-kg object is at rest at the origin of a coordinate system. A 3.0-N force in the +x-direction acts on
the object for 1.50 s. (a) What is the velocity at the end of this interval? (b) At the end of the interval, a
constant force of 4.0 N is applied in the –x-direction for 3.0 s. What is the velocity at the end of the 3.0 s?
Plan: Do the problem by using impulse and momentum concepts.
Show your work:
Answer the question: Be sure to include units.
Evaluate:
Do a unit analysis (if you didn’t do one above).
Is the magnitude of the answer reasonable? Is it the same as you calculated following
the other plan?.
Phy 101: HW6: Fall07
Eyres
Homework Assignment 6:
Due beginning of class
Name:
#2. Chapter 6: Problem #40 (Underline or highlight the question.)
An 8.00-kg object moving east at 15.0 m/s on a frictionless horizontal surface collides with a 10.0-kg
object that is initially at rest. After the collision, the 8.00-kg object moves south at 4.00 m/s. (a) What is
the velocity of the 10.0-kg object after the collision? (b) What percentage of the initial kinetic energy is
lost in the collision?
Plan: Begin with filling out the component chart for momentum. List all the equations
that you might need to consider in doing this problem.
Show your work:
Object Description
Momentum Vector
x-component of
momentum
8.0 kg object initial
10.0 kg object
initial
8.0 kg object final
10.0 kg object final
Write your equations and solve:
Answer the question: Be sure to include units.
Evaluate:
Do a unit analysis (if you didn’t do one above).
Is the magnitude of the answer reasonable? Give a reason.
Phy 101: HW6: Fall07
Eyres
y-component of
momentum