6.8BCD: Changes in Force and Motion

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6.8BCD Changes in Force and Motion Force,
Motion, and Energy
1 A game of tug-of-war, in which two teams pull on opposite ends of a rope, is illustrated here. The center of the rope will move when which of the following is true? A game of tug-of-war, in which two teams pull on opposite ends of a rope, is illustrated here. The center of the rope will move when which of the following is true?
A The ground provides no friction for either team
B One team has more people than the other
C The rope has essentially no mass of its own
D One team pulls with more force than the other
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6.8BCD Changes in Force and Motion Force,
Motion, and Energy
2 If the distance an object travels and the time it takes to travel the distance are known, which of the following can be calculated? If the distance an object travels and the time it takes to travel the distance are known, which of the following can be calculated?
A Average speed
B Average acceleration
C Instantaneous speed
D Instantaneous acceleration
3 Students are graphing data they recorded of a marble rolling across the floor in the classroom. Which of the following accurately describes a correct assignment of a label to the graph? Students are graphing data they recorded of a marble rolling across the floor in the classroom. Which of the following accurately describes a correct assignment of a label to the graph?
A Distance in Centimeters on the y-axis
B Time in Inches on the y-axis
C Distance in Minutes on the x-axis
D Time in Meters on the x-axis
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6.8BCD Changes in Force and Motion Force,
Motion, and Energy
4 If an object travels 42 meters in 6 seconds, what is its average speed? If an object travels 42 meters in 6 seconds, what is its average speed?
A 6 m/s
B 7 m/s
C 48 m/s
D 252 m/s
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6.8BCD Changes in Force and Motion Force,
Motion, and Energy
5 Two horses pull in opposite directions, but together move in the direction shown. Which of the following best describes the forces being applied in this situation? Two horses pull in opposite directions, but together move in the direction shown. Which of the following best describes the forces being applied in this situation?
A The forces are balanced, and the net force is zero
B The forces are unbalanced, and the force of Horse 1 is greater
C The forces are unbalanced, and the force of Horse 2 is greater
D The forces are balanced, and the force of Horse 1 is greater
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6.8BCD Changes in Force and Motion Force,
Motion, and Energy
6 What is the average speed of a toy car that travels 240 cm in one minute? What is the average speed of a toy car that travels 240 cm in one minute?
A 4 centimeters per second
B 15 centimeters per second
C 40 centimeters per second
D 240 centimeters per second
7 What motion will result from two forces acting on an object one force of 50 Newtons to the east, the other a force of 30 Newtons to the west? The object will What motion will result from two forces acting on an object one force of 50 Newtons to the east, the other a force of 30 Newtons to the west? The object will
A move east at a constant speed.
B accelerate to the east.
C move west at a constant speed.
D accelerate to the west.
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6.8BCD Changes in Force and Motion Force,
Motion, and Energy
8 Which graph represents an object moving at the greatest speed? Which graph represents an object moving at the greatest speed?
A
B
C
D
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6.8BCD Changes in Force and Motion Force,
Motion, and Energy
9 Which of the following is the correct formula for calculating speed? Which of the following is the correct formula for calculating speed?
A Speed force/distance (force divided by distance)
B Speed mass x acceleration (mass times acceleration)
C Speed distance/time (distance divided by time)
D Speed time x energy (time times energy)
10 A motorcycle traveled 250 kilometers in five hours. What was its average speed in km/hr? Record and bubble in your answer on the grid provided below.

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