Motion And Pressure Flashcards
When an object is increasing its speed this is known as?
Acceleration
Define atmospheric pressure
Pressure caused by the collisions of air molecules that produce a force on an area
Why are dams built thicker at the bottom that the top?
Because water pressure increases with depth
State the equation linking distance travelled, speed and time taken
Speed = distance/time
State the equation which links area, force and pressure
Pressure = force/area
What does a curved line on a distance-time graph represent?
An object speeding up or slowing down
_____ _____ means how fast one thing is travelling compared to another
Relative motion
What units is speed measured in?
Metres per second (m/s)
What is pressure measured in?
Newtons per metre squared (N/m2)
Define the word compress
To squash into a smaller space
State the equation for calculating average speed
Average speed = total distance/total time
What is the density of an object?
The mass of material in a given volume
For floating objects, the upthrust is equal and opposite to the object’s…?
Weight
What is liquid pressure?
The pressure produced by liquid particles pushing on each other and on surfaces
Why is it not possible to compress a liquid?
The particles are touching so cannot be pushed closer together
Why is atmospheric pressure greater closer to the surface of the earth?
Gravity pulls air particles towards the earth meaning that particles here are closer together and collide with surfaces more frequently exerting a higher pressure
What does a straight line sloping upwards on a distance-time graph represent?
An object travelling at a constant speed
Why can gases be compressed?
There is lots of empty space between particles so they can be pushed closer together
What is speed?
A measure of how far something travels in a given time
What are the units of density?
Grams per metre cubes (g/m3)
Is it possible to compress a gas?
Yes
What is gas pressure
The force exerted over a certain area by a gas
Is it possible to compress a liquid?
No
