Forces and Pressure

Acceleration Positive - Acceleration Negative - Deceleration Measured in m/s/s or m/s2 -How quickly you change speed Force Force = mass*acceleration Measured in Newtons (N/m2) or (N/cm2) Air resistance = gravity (constant speed) Air resistance < gravity (acceleration) Air resistance > gravity (deceleration)If forces are balanced, constant speedUnit L: Pressure Pressure = Force/Area Measured in Pascals (Pa) 1 Pa = 1 N/m2 In air, pressure decreases as you get higher because less of the weight of the air is above you. In water, pressure increases as you get lower. Pressure in fluids are the same in everywhere. Fluids = Liquid and gases Compression = Gas being squashed closer together (air molecules are more spread out and move around more)Hydraulic systems Force multiplier: Input force < Output force However, the piston on the other end moves less if Input force < Output force. A lever can be used to apply a force which turns something around a pivot. Moment = Turning effect of a force Measured in Newton Metres (N m). Force (N) * distance from pivot (m) = Moment