UNIT 2

PHYSICS I - UNIT 2

HW	MECHANICS: DYNAMICS	Read	Problems	Supplement
11	Newton's 1st law of motion, forces	87-89	Pg 104 RC2,8	1,2,3
12	Newton's 2nd law of motion	90-91	Pg. 106 P 4-7	6
13	Newton's 3rd law of motion	92-93	Pg. 106 P 9-10	7,8,9
14	Weight and mass, gravitational & inertial mass	93-96	Pg 106 P 11-13	5
15	Net force causes acceleration	98-102	Pg 106 P 17-21
16	Dry friction Drag	96-97 102-103	Pg. 107 P 22-24	4
17	Summary of dynamics

Supplementary Questions:

1. A student rides a bus. Use Newton’s First Law to explain each of the following:

a) The student moves forward as the bus starts.

b) The student moves backward as the moving bus starts.

c) The students moves to the side as the bus makes a turn.

2. Use Newton’s First Law to explain why seat belts are needed when riding in a car.

3. Compared to the inertia of a ¼ kg mass the inertia of a 1.0 kg mass would be _________ as great.

4. A 100 newton box rests on a horizontal surface. A force of 10 newtons parallel to the surface is required to start the box moving. What is the coefficient of static friction between the box and the surface?

5. What is the mass of a 6.0 kg object on the moon if the force of gravity of the moon is one-sixth that of the Earth? Explain your answer.

6. A force of F on a mass M causes an acceleration of 8 m/s². What acceleration will result from a force of 2 * F on a mass of one-fourth M?

7. Define Newton’s Third Law.

8. Use Newton’s Third Law to explain: A car will not move if the wheels are on ice.

A bag weighing 10 N is placed on a table. What is the force that the table exerts on the bag?

HW#	Title	Read	Problems	Supplement
18	Introduction to Vectors	109-112	128 RC3 pg129P1-5,26
19	Composition of Forces	109-112	130-131P15-10
20	Resolution of Vectors	116-19	130 Prob. 21,22, 36
21	Equilibrium	120-122	131 Prob. 29-32
22	Inclined Planes	123-126	131 Prob. 34, 35abc;36
23	Summary of Statics		692 prob. 4, 6acef,14,

Test #2