4- Streamlining

Question 1

what happens when a car has a very unstreamlined shape?

Answer 1

the car has to push air particles out of the way, and the particles cannot flow around the car as easily, so there is more air resistance which means the car needs to create a larger driving force.

Question 2

what happens when a car IS very streamlined?

Answer 2

air particles can flow easily over the car, so there is less air resistance, which means the car does not need to produce such a large driving force

Question 3

when you (e.g) ride a bike, what is the main friction force acting on you?

Answer 3

the drag force

Question 4

why do space shuttles get so hot when they enter the earth’s atmosphere?

Answer 4

the shuttle collides with lots and lots of air particles as it passes into the atmosphere. this produces such a large drag force that it gets hot and burns up.

Question 5

what do drag forces depend on, and why?

Answer 5

drag forces are dependent on speed; the faster something moves, the more air hits the object per second, so the more air resistance slows it down.