5.6D Force and Motion Experiments

What is friction?

• Force applied against motion. Slows the motion down.

• Force applied with motion. Speeds the motion along.

What is the dependent variable? (the thing she is going to measure as a result)

• How far the object rolls

• what type of surface the object is rolling on

• height of the ramp

Why do both ramps need to be at the same height?

• The need to be at the same point so we can measure accurately and to be able to compare the measurements.

• They don't need to be at the same height. Start anywhere you like.

What ramp do you think will cause the glue stick to roll faster? Why? 

• The ramp with bumps because the bumps will help the glue jump over the ramp.

   

• The ramp without bumps because the surface is smooth and doesn't slow down the objects.

Notice, she is going to use the SAME object on the second ramp. Why??

• She is using the same object with the different textured ramp because the question we are trying to answer is "Will the different surface texture of the ramp affect how far my objects roll?"

• She is using the same object with the different textured ramp because the question we are trying to answer is "Will the different object affect how far my objects roll?"

What can you guess happened the second time?

• the glue stick rolled farther than it did on the smooth ramp

• the glue stick rolled less than it did on the smooth ramp

 

A ball is rolling across the surface, but it eventually comes to a stop. Which force is most likely responsible for this?

• gravity

• electricity

• friction

• magnetism

Looking at the picture, what two tools would be needed to measure the effect of friction on the ball?

• hand lens and balance

• balance and spring scale

• spring scale and hand lens

• measuring tape and stop watch

When conducting an experiment, in order to get reliable results, it is important to:

• Disregard results that do not match you hypothesis.

• Test many different variables at the same time.

• Repeat the investigation several times with only 1 different variable.

• Test all forces at the same time.

When designing an experiment, why is it important to test only one variable?

• Testing one variable explains what caused the change once data has been gathered.

• Testing one variable decreases the reliability of the investigation.

• Testing one variable collects inaccurate data and repeat the investigation more than necessary.

• It is not necessary to test only one variable.