Sci. y2 Phy. 3 ( Speed & Pressure )

• Speed is measured in meters per second
• Instantaneous speed is the speed at a particular moment
• average speed is the total distance over the total time taken
• the difference in speed between 2 objects is called relative motion
• A distance time graph shows the distance that an object travels in a certain time
• A gas exherts a pressure on the walls of its container because particles colide with the walls
• If a gas gets hotter pressure will be bigger
• If the volume gets bigger pressure will be smaller
• As you go up a mountain the air pressure will be smaller, because there are fewer air particles
• As you pump more gas into a container the gas becomes compressed
• The air exherts a pressure on you body the entire time, called atmospheric pressure
• The pressure in liquids acts in all directions
• The pressure increases as you go deeper, because the weight of the water above you gets bigger
• The force that keeps things a float, is called upthrust
• When an object floats there are more water particles hitting the bottem than air particles are hitting the top
• Pressure is measured of how much force there is on a certain area
• Big force + small area = large pressure
• Big force + big area = small pressure
• Speed (M/S) = Distance (m) / Time (s)
• Distance (M) = Speed (m/s) x Time (s)
• Time (S) = Distance (m) / Speed (m/s)
• Pressure (n/m^2) = Force (N) / Area (m^2)
• Force (n) = Pressure (n/m^2) x Area (m^2)
• Area (m^2) = Force (n) / Pressure (n/m^2)