Rachael's Site It can't be done the night before it's due? Challenge Accepted.

# Scientific Application!

## Purpose:

What we are trying to figure out is; When we change the gradient of a slope how does that change the amount of work that we need to pull an object up the slope?

My hypothesis is that when we change the gradient of the slope it changes the amount of work we need to pull the object up the slope. We are trying to see when we lifted an object such as a stapler straight up in the air how much work that took, opposed to when you we used an inclined planes to bring the same object the same distance up into the air. I think that when we change the gradient of the slope it changes the force because if a slope is very steep like a steep set of stairs this is surly harder to climb than a gently sloping set of stairs.

## Variables:

The variables that we used were the work. We got this variable by multiplying the effort force and the effort distance of an object. The work was the dependent variable and the other variable was the slope. We figured this out by dividing the slope’s rise by its run. These are variables because they can change. The work changes with every new slope you use and the slope changes because you have to change the gradient of each slope.

Two controlled variables are the rise of the slope because we always wanted the rise to be 0.1 meters high. And we always wanted the object that we were pulling up the slope to stay the same weight. We used a stapler as our object and each time we had to take all the staples out of it it incase somebody used a staple which would have slightly changed the weight of the stapler. We never wanted the stapler to change its weight because if its weight did change the effort force would change as well and this could have changed our data completely.

## Method: Photo journal of how we did our experiment:

This was one of our slopes and we were measuring the run of this slope.

This was one of our slopes and we were measuring the rise of the slope in this picture.

This was us measuring the force that it took us to pull the stapler up the first slope.

This was when we had to the measure how much force it first took us to pull a stapler straight up in the air opposed to using a slope.

This was us measuring the run of the slope.

This was when we were measuring the rise of the slope making sure that it was always 0.1 centimetres and therefore how far we had to pull the stapler up the slope:The effort distance it had to travel.

This is me measuring the effort distance we had to take the stapler up the slope.

# Evaluation:

## How certain and uncertain were the measurements you made?:

How many times did we measure or re-measure the inclined planes so was our experiment fair?

We measured all of our measurements only once. So to improve our experiment the next time we will measure all of our measurements more than once just to make sure that our measurements are precise. I think our measurements of the effort force and the effort distance were quite uncertain because I feel that we should have re-measured these calculations more than once to make sure we had measured these distances correctly. The reason I think we did not measure the effort force correctly is because comparing this experiment to our last investigation, which was extremely similar to this one, when we measured the effort force it was always a whole number. But in this investigation when we measured the effort force it was always small decimals. I’m not to sure that we measured them correctly and this is why I think our data was not very close to the “ideal data”.

## How fair and unfair was our experiment?:

The controlled variables were the rise of the inclined plane and the inclined plane. Our experiment was unfair because I don’t think we always kept the rise of the inclined plane at 0.1 meters. I think that we should have measured the inclined plane’s rise more precisely. I feel that when we were measuring it we were not as precise as we needed to be and we may not have always kept the rise at exactly 0.1 meters. Another one of our controlled variables was the stapler’s weight because in order to find out how much the stapler’s effort force changes per slope we needed it to weigh the same amount every time. We kept the staplers weight the same by taking the staples out of it before we began each phase of the experiment.

I think that when we were measuring the effort force of the stapler we somehow measured it incorrectly because comparing this experiment to the one we did last time, the effort force of the object was always a whole number but this time when we measured the effort distance they were not whole numbers they were very small decimals.

How could we make our experiment more fair?

I think that next time we could make the variables more fair by measuring the rise and the run which we needed in order to figure out the slope more accurately. We measured them quite accurately this time but next time we could be more specific. If the run was say 11.3 centimetres we just rounded the slope to 11 centimetres and I think we should have used the exact values. The item we measured the effort force of was a stapler. Next time I think we could pick a different item because this item was quite tricky to work with. In order to make sure it was the exact same weight every time we used it, we had to take the staples out of it. So next time, not only to improve the experiment I would choose a different item to use.