Velocity, speed and acceleration 5m/s velocity 5m/s North East Velocity is speed in a given direction 5m/s speed 5m/s going round An object moving at a steady speed is accelerating if its direction is changing

Acceleration = change in velocity (m/s) time (s) (m/s/s) Acceleration is the change in velocity each second. eg What is the acceleration of the cyclist? Initial speed = 8 m/s final speed = 20 m/s time taken = 6 sec acceln = v = 12 m/s t 6 s = 2m/s/s

Acceleration = change in velocity (m/s) time (s) (m/s/s) Acceleration is the change in velocity each second. eg What is the acceleration of the cyclist? Initial speed = 8 m/s final speed = 20 m/s time taken = 6 sec acceln = v = 12 m/s t 6 s = 2m/s/s

Acceleration = change in velocity (m/s) time (s) (m/s/s) Acceleration is the change in velocity each second. eg What is the acceleration of the cyclist? Initial speed = 8 m/s final speed = 20 m/s time taken = 6 sec acceln = v = 12 m/s t 6 s = 2m/s/s

Initial speed = 8 m/s final speed = 20 m/s time taken = 6 sec acceln = v = 12 m/s t 6 s = 2m/s/s Calculate these accelerations: Q1. A motor bike accelerates from 10m/s to 20m/s in 2 sec. Q2. Concorde accelerates from rest to 40m/s in 10 sec. Q3. A wasp accelerates from 2m/s to 6m/s in 1sec.

Velocity (m/s) 10 5 Acceleration is the gradient or slope of a velocity : time graph. b a c 0 5 10 15 20 25 time / s

a b c Velocity (m/s) 10 5 0 5 10 15 20 25 time / s Acceleration is the gradient or slope of a velocity : time graph. a. Steady Acceleration: acceln = v = t

a b c Velocity (m/s) 10 5 0 5 10 15 20 25 time / s Acceleration is the gradient or slope of a velocity : time graph. a. Steady Acceleration: acceln = v = 10 m/s = 2 m/s/s t 5 s

a b c Velocity (m/s) 10 5 0 5 10 15 20 25 time / s Acceleration is the gradient or slope of a velocity : time graph. a. Steady Acceleration: acceln = v = 10 m/s = 2 m/s/s t 5 s b. Uniform Velocity:

a b c Velocity (m/s) 10 5 0 5 10 15 20 25 time / s Acceleration is the gradient or slope of a velocity : time graph. a. Steady Acceleration: acceln = v = 10 m/s = 2 m/s/s t 5 s b. Uniform Velocity: 10m/s ( zero acceln )

a b c Velocity (m/s) 10 5 0 5 10 15 20 25 time / s Acceleration is the gradient or slope of a velocity : time graph. a. Steady Acceleration: acceln = v = 10 m/s = 2 m/s/s t 5 s b. Uniform Velocity: 10m/s ( zero acceln ) c. Steady deceleration: (- ve Acceleration) acceln = v = - t

a b c Velocity (m/s) 10 5 0 5 10 15 20 25 time / s Acceleration is the gradient or slope of a velocity : time graph. a. Steady Acceleration: acceln = v = 10 m/s = 2 m/s/s t 5 s b. Uniform Velocity: 10m/s ( zero acceln ) c. Steady deceleration: (- ve Acceleration) acceln = v = -10 m/s = -1 m/s/s t 10 s

The distance travelled is the area under a v:t graph. Velocity m/s 10 5 0 5 10 15 20 25 time / s

The distance travelled is the area under a v:t graph. Velocity m/s 10 5 b a c 0 5 10 15 20 25 time / s

The distance travelled is the area under a v:t graph. Velocity m/s 10 5 5 x 10 = 25m 2 b a c 0 5 10 15 20 25 time / s

The distance travelled is the area under a v:t graph. Velocity m/s 10 5 5 x 10 = 25m 2 b 10 x 10 = 100m a c 0 5 10 15 20 25 time / s

The distance travelled is the area under a v:t graph. Velocity m/s 10 5 5 x 10 = 25m 2 b 10 x 10 = 50m 2 10 x 10 = 100m a c 0 5 10 15 20 25 time / s

If investigating how the slope of a runway affects a trolley’s acceleration: a) Name 1. The independent variable 2. The dependent variable b) What is the relationship between the variables?

If investigating how the slope of a runway affects a trolley’s acceleration: a) Name 1. The independent variable 2. The dependent variable b) What is the relationship between the variables?

a) Name 1. The independent variable 2. The dependent variable Distance from sensor Time If investigating how the slope of a runway affects a trolley’s acceleration: a) Name 1. The independent variable 2. The dependent variable b) What is the relationship between the variables?

B A D C A C A - has the largest area under the graph C - has the smallest area under the graph

Which car has the highest acceleration? X or Y Y - has the steepest slope

is constant. of an object decreases. speed acceleration speed ∆ v = 28 - 8 = 20m/s a = ∆ v = 20 ∆ t 8 = 2.5 m/s/s

accelerates steady steeper steeper slope speed : time ticker tape trolley.