AIM: How do we solve Friction, Forces and Gravity problems? DAY 4: Forces & Gravity Activity SheetsOBJ: Given activity sheet and video SWBAT solve friction, forces and gravity problems with 70% accuracy.

DN: Take out Friction 3 and Friction Activity Sheets

ACT: Review Results: Friction 3 and Friction Activity Sheets.Complete Forces (Q: 2, 4, 9, 10 only) and Gravity Activity Sheets

HW: Complete 3 types of Motion and What makes things fall Activity Sheets; Study for SFFG Exam; SFFG Exam, Thursday April 30; NLSM Exam, May 28?

Friction 3 Activity Sheet-A.K.1. 16N

2. Because it makes it easier to move the object; Certain objects can be very heavy and because static friction is more than sliding, rolling and fluid friction.

3. When metal parts are rubbing (scraping) against each other (ex: watch, engine)

4. more

5. less; reduced

6. lubricant

7. reducing

Friction 3 Activity Sheet-A.K.1. decreases

2. less

3. more (more roughness)

4. less (more smoothness)

5. is

6. increasing

7. increase

8. greater

b

Friction Activity Sheet-A.K.1. 4 2. 4 3. 4 4. 4 5. 40 joules

6. least amount of friction; energy input is closest to energy output which shows an increase in efficiency.

7. spring scale

8. glue/attaching sandpaper to table; make table surface rough; adding additional mass/weight to block

9. reduces friction by rolling friction

Forces Activity Sheet-Answer Key

1. 3

2. 1

3. 2

4. 2

5. 2

6. 3

7. 2

8. 2

9. 3

10. 2

Gravity Activity Sheet-A.K.1. 1

2. 4

3a. A

3b. The closer the distance, the more the gravity

3c.

4. B will move; B may hit another satellite; B may crash to earth; B may fly out into space

Gravity Activity Sheet-A.K.4.More mass (larger size) ~ stronger the gravitational pull; less mass (small size) ~ weaker the gravitational pull.

5. Mercury, Mars, Pluto

6. Pull the bow string farther (more)

7. Gravity pulls arrow down so that the trajectory (path) is curve/arc–shaped.