Student Email: 1024885@wells-school.com
Site Title: Pearson Physics - Welcome to the eTest Companion Site
Location on Site: U3: Circular Motion, Work, and Energy > Chapter 6 > Section 6.2 eTest
30% Correct of 10 Scored items:
3 correct: 30%
7 incorrect: 70%
Submitted on December 12, 2012 at 8:13 PM (UTC/GMT)
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Question 1
Mechanics involves the study of forces in equilibrium, the study of motion, and the study of non-zero forces and the motion that results from them.
Which of the following is not an area of study under mechanics?
Correct: Workonics
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Question 2
By what must a change in kinetic energy always be accompanied?
Correct: A change in speed
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Question 3
Use the following information to answer the next 2 questions.
Many trucks are equipped with winches. These winches are motor-powered spools that can be latched onto heavy loads, making it possible to pull them easily. Suppose a winch is used to pull a car up a slippery incline at a constant speed of 2.0 km/h.
Consider this situation of winching a car. Which of the following is false?
Incorrect: The truck is exerting a zero net force on the car.
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Question 4
Suppose that the electrical current to the winch is increased, causing the car being pulled up a slippery slope to accelerate. Which of the following mathematical expressions does not represent the situation?
Incorrect:
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Question 5
A circus performer, with a mass of 140 kg, is flung from a catapult. At the peak of his trajectory his horizontal speed is 50 m/s and he is 300 m above the ground. With the ground as a reference point, what is the mechanical energy of the performer at the highest point in his trajectory?
Incorrect: 4.1 x 105 J
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Question 6
Choose the only answer that can complete the following statement. The work energy theorem states that ____________.
Incorrect: the work done on a system is always the change in its kinetic energy.
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Question 7
Which of the following statements concerning energy and energy change is true?
Incorrect: A change in kinetic energy can be accomplished without changing speed.
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Question 8
Imagine that you are taking a flight to Vancouver. You have a mass of 65 kg, begin at ground level, and are stationary. Later, at a particular point over the Rockies your body is 16 000 m above ground level and is travelling at 100 m/s.
Which of the following best describes the mechanical energy of your body?
Correct: Your body possesses much more gravitational potential energy than kinetic energy.
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Question 9
A lead shot fired from a shotgun has 200 J of kinetic energy. If it is travelling at 200 m/s, what is the mass of the lead shot?
Incorrect: 100 g
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Question 10
Choose the only answer that can complete the following statement. In order for work to be performed in a system, ___________.
Incorrect: a change in kinetic energy is required.
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