Car At 55 Mph
by:Stephanie Sanda

*The Question*external image ktm_race_car.jpg
-What happens to make a car travel at 55 mph? What forces makes the car slow down?

*The info*

-For a car to speed up or slow down, the forces on the car must change, there must be a net force going forward that’s speeding the car up to 55 mph.

-When a car hydroplanes it effects the net force on the car causing it to go away, the friction between the car and the road is broken causing the force to decrease and car to slow down. The engine is also effected because there is less of a grip on the tires to the road so engine power is wasted which means there is smaller drive force pushing the car forward to accelerate to 55 mph.
external image car-driving.jpg
-When a car hydroplanes it effects the net force on the car causing it to go away, the friction between the car and the road is broken causing the force to decrease and car to slow down. The engine is also effected because there is less of a grip on the tires to the road so engine power is wasted which means there is smaller drive force pushing the car forward to accelerate to 55 mph.
-But if the decrease in frictional force is greater than the decrease in drive force the car will speed up and accelerate to the speed the car is set to in this case 55 mph.
-If the decrease in frictional force is smaller than the decrease in drive force the car will slow down.
-When you’re in a moving car you experience inertia all the time. Seatbelts exist in cars to counteract the effects of inertia, think for a moment that a car traveling at 55 mph, and a person is inside of the car in the front seat. If the car happens to slam into a wall the person in the front seat of the car fly’s forward into the dashboard. Because, according to Newton’s First Law an object in motion will remain in motion until an outside force acts on it. When the car hits the wall the person keeps moving in a straight line and at the same speed as the car was going flies forward into the dashboard. So seat belts hold passengers down protecting them from their own inertia.

Video From www.youtube.com -http://www.youtube.com/v/xlfSkP4w9qU&hl=en_US&fs=1&rel=0&color1=0x006699&color2=0x54abd6"></param><param

Bibliography

Picture- http://blog.xkmph.com/wp-content/uploads/2008/12/ktm_race_car.jpg
Picture # 2- http://www.esafetysupport.org/images/photos/car-driving.jpg
Video- www.Youtube.com
Information- http://science.howstuffworks.com/newton-law-of-motion1.htm
and http://www.physicsclassroom.com/class/1dkin/u1l1d.cfm
i also had information from my notes.