Forces And Pressure On Solids Flashcards
what are balanced forces
forces that are the same size but work in opposite directions.
If forces are balanced:
a stationary object stays stationary
a moving object continues to move at the same speed.
how does a car or motorbike move at a steady speed
uses the energy stored in the fuel because it needs the force from the engine to balance air resistance and friction.
how can air resistance be reduced
by giving the object a smooth streamline shape
as the speed increases…
the air resistance increases
how is air resistance caused
by air particles hitting a moving object
why can objects get hot when they move through the air
because particles transfer energy to the object
what is pressure
the amount of force pushing on a certain area
for a certain area, the bigger the force…
the bigger the pressure
for a certain force the bigger the area…
the smaller the force
why does a pin go into the wall and not the thumb
The point has a very small area, so there is a very
large pressure on the board, and the pin goes in.
The area of the thumb is much larger than the area of the pin point, so there is only a small pressure on the board.
pressure of a knife
a small area giving a large pressure
