Acceleration and gravity

Acceleration Measure of the rate at which an object’s velocity is increasing (or decreasing). Units: metres per second per second (m/s/s or m.s -2 ). Formula: acceleration = change in velocity ÷ change in time a = Δv/Δt

Gravity Gravity is a force which makes a free falling object accelerate. On Earth the force of gravity makes at object accelerate at about 10 m.s -2. This means that the velocity of an object increases by 10ms -1 every second it falls. It doesn’t matter what the mass of an object is. It falls at the same rate. 68LyZM 68LyZM Feather and hammer on the moon: 7E 7E

Felix Baumgartner Felix Baumgartner jumping from the edge of space: Gd4 Gd4 An object falling in Earth’s atmosphere will accelerate until an opposing force (air friction or drag) equals the force of gravity. The maximum speed of a falling object in the atmosphere is called terminal velocity:

Force and mass A force is a push or a pull (a twist is a combination of both). A force applied to an object in the absence of friction will make the object accelerate. The larger the force, the greater the acceleration. The larger the mass of the object, the smaller the acceleration. Formula: Force = mass x acceleration, F=ma vw vw

Practical applications Small car vs Big car: E E mi0 mi0 The best two ways to increase acceleration of any object is to decrease mass and increase the force.

Friction Friction is a force that opposes motion. Friction converts kinetic energy into heat energy. Reducing friction increases both acceleration and also the maximum speed an object can travel on Earth. Remember: Friction is not a factor that needs to be considered with moving objects in space.

Applications of friction reduction Cycling: aUOzYAuL48https:// aUOzYAuL48 The worlds fastest Indian: IKs IKs