4. Results and Discussion

Activity 1

Area fsmax fk

1 0.8 N 0.6 N2 0.6 N 0.2 NTable 1. Friction and Area of Contact

Activity 2

Weight of block = 2.2 Newtons

Normal Force fsmax fk μs μk

3.2 N 1.0 N 0.6 N 0.31 0.194.2 N 1.6 N 1.4 N 0.38 0.335.2 N 2.0 N 1.6 N 0.39 0.312.2 N 0.8 N 0.6 N 0.36 0.27

Table 2. Friction and Normal Force

Activity 3

Surfaces in Contact fsmax fk

Wood and wood 0.8 N 0.6 NWood and sand paper 0.6 N 0.4 N

Wood and plastic cover 0.6 N 0.4 NWood and cartolina 0.8 N 0.2 NTable 3. Friction and Nature of Surface of

Contact

Activity 4

ObservationRub hands for 1

minuteFeels the hottest on the skin than with lotion and powder

Rub hands with lotion for 1 minute

Feels hotter on the skin than with powder

Rub hands with powder for 1 minute

Feels hot on the skin

Table 4. Effect of Lubricants

Activity 5

Table 5. Air Resistance

1

Number of Filters

Terminal Velocity

Square of Terminal Velocity

1 -0.9109 m/s 0.8297 m2/s2

2 -1.214 m/s 1.474 m2/s2

3 -1.363 m/s 1.858 m2/s2

4 -1.553 m/s 2.412 m2/s2

5 -1.752 m/s 3.070 m2/s2

2