Friction. That was the topic Sally and Sue are investigating in science. They used a small car and a ramp as seen in the picture above. They knew that they slipped easily on waxed floors but not on carpet, so they decided change the
material on the surface of the ramp. They planned to use glass, carpet, aluminum foil, and sandpaper and run the car
down the ramp over each surface. The girls wrote a research question: Do rougher surfaces tend to create more
friction than smoother surfaces? They predicted that the greater the friction, the slower the car would travel down the
ramp
What would be the BEST hypothesis for their experiment?
A)
The smoother the ramp surface, the greater the car's speed.
B)
Heavier cars travel down the ramp faster than lighter cars.
The greater the angle of the ramp, the faster the car will move.
D)
Without lubrication, the car will travel slowest down the sandpaper
covered ramp.