3.1 Investigate the Relation between Force of Limiting Friction and Normal Reaction to Find the Co-efficient of Sliding Friction between a Wooden Block and a Horizontal Surface
Observations and Calculations
Weight of empty pan=W3=0.4N
| No | Weight of the block w1 (N) |
Weight placed on the block w2 (N) |
Normal Reaction R=w1+w2 (N) |
Weight placed in the pan w4 (N) |
Friction force fs=w3+w4 (N) |
Coefficient of friction μs=fs/R |
| 1 | 0.50 | 0.3 | 0.80 | 0.5 | 0.9 | 1.125 |
| 2 | 0.50 | 1 | 1.50 | 1.4 | 1.8 | 1.2 |
| 3 | 0.50 | 1.5 | 2.00 | 1.9 | 2.3 | 1.15 |
Average μs=1.158
Result
The value of Co-efficient of Sliding Friction between a Wooden Block and a Horizontal Surface is 1.158.
3.2 Find the Force of Limiting Friction by Rolling a Roller on a Horizontal Surface
Observations and Calculations
Weight of pan=w1=m1g=0.8N
value of g=10ms-2
| No. | Weight placed in the pan w2=m2g (N) |
Limiting Friction= Total weight =m1g+m2g (N) |
| 1 | 0.50 | 1.3 |
| 2 | 1 | 1.8 |
| 3 | 1.5 | 2.3 |
Average value of Limiting friction=1.8N
Result
Value of limiting friction for the roller on the horizontal plane is 1.8N.