Chapter 3 Newton’s First Law of Motion HW 8, 10-13, 16-17, 20-22.

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Transcript of Chapter 3 Newton’s First Law of Motion HW 8, 10-13, 16-17, 20-22.

Chapter 3

Newton’s First Law of Motion

HW 8, 10-13, 16-17, 20-22

8. What name is given to the property of an object to resist changes in motion?

Inertia

10. What is the tendency of an object at rest when no forces act on it?

To remain at rest.

11. What is the tendency of a moving object when

no forces act on it?

To continue moving in a straight line at a constant speed indefinitely.

12. What relationship does mass have with inertia?

Mass is a measure of inertia; the more mass an object has, the more inertia it has.

13. What does it mean to say mass and weight are proportional to each other?

If one increase or decreases, the other changes in the same way.

1 kg to 10 kg

2.2 pounds to 20.2 pounds

16. What is the standard (or SI) unit for mass?17. What is the standard (or SI) unit for weight?

For mass it is kilograms (kg) For weight it is newtons (N)

20. If you’re in a smooth-riding bus that is going at 40 km/h, and you flip a coin vertically, how fast does the coin move horizontally while in midair?

The coin’s horizontal speed is the same as the speed of the bus, 40 km/h, which is the same speed for you, as well.

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21. a. Greatest to least resistance to change

in motion BACD b. Greatest to least weight BACD c. greatest to least normal support BACD

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22. a. Greatest to least force required to

keep them going A=B=C (no force) b. Greatest to least force required to stop

them in the same time interval CBA