Friction – Friend or Foe

aim-

To hypothesise and test what types of surface cause the most

friction.

hypothesis-

I presume that the roughest surface (eg. cement ) t will produce the most friction.

equipment-

-1x Newton Spring Balance -1x Block of Wood
-Different Surfaces [ e.g. ice, grass, dirt, etc. ]

independent

variables-

I will change the surfaces.

dependent

variables-

I will record what surface causes the most friction.

control

variables-

I will keep the spring balance, block of wood and the

Distance the block of wood will travel to ensure a fair

test.

method-

-First of all you will need all the Equipment listed

-Then take the block of wood and attach it to the spring balance

-Then you must drag the spring balance with the block of wood behind it

-Record the reading on the spring balance for each surface

-Repeat the dragging and recording process 3 times for each surface

-Then work out the average friction by adding all results for each surface and

-The surface with the highest average overall has produced the most friction

results-

Surface

Ice Cement Wood Grass Dirt

Trial 1 – 0.1 0.5 0.35 1.2 1.0

Trial 2 - 0.12 0.6 0.5 1.0 0.8

Trial 3 - 0.12 0.6 0.4 1.0 0.9

Average- 0.12 0.6 0.4 1.0 0.9

discussion-

SHAPE * MERGEFORMAT
1.0 Newtons-

0.9 Newtons-

0.8 Newtons-

0.7 Newtons-

0.6 Newtons-

0.5 Newtons-

0.4 Newtons-

0.3 Newtons-

0.2 Newtons-

0.1 Newtons-

0.0 Newtons-

Ice Cement Wood Grass Dirt

-What I hypothesized was that the cement would produce the most

friction. I was quite wrong, the grass actually produced the most

friction and not the cement.

-What I observed during my investigation did make sense according

my results. My results indicated that the most ‘uneven’ surface

produced the most friction and not the roughest as I guessed.

-Some surfaces [ the ice for example ] did not produce as much

friction [ as say the cement ] because it is a lot smoother. The

reason the grass produced the most friction was because the

surface was so uneven therefore it wasn’t easily pulled along the

distance.

-Some difficulties I experienced during my investigation were

inaccurate spring balances. They sometimes did not keep a

constant measure.

much more accurate then what they were. Also if the block of wood

had been carried a longer distance it would make for a more