3.1 Motion Flashcards
Equation for speed
Average speed = Distance traveled/ Time taken
Equation for velocity
Average velocity = total displacement/ time taken
Equation for acceleration
Acceleration = change in velocity/ time taken
What does the gradient on a displacement-time graph equal?
The velocity
What does the gradient of a velocity-time graph represent?
Equal to the acceleration
What does the area beneath a velocity-time graph represent?
Equal to the displacement of the object
What would would happen to a body if a resultant force was acting on it?
The body would accelerate or deccelerate
What are the SUVAT equations?
v = u + at s = ut + 1/2at^2 v^2 = u^2 + 2as s = 1/2(u + v)t
Why do objects of different masses fall at the same rate?
This is because acceleration of an object is directly proportional to the force acting on it, but inversely proportional to it’s mass.
What are the two approaches that can be used to measure the acceleration of free fall?
. Direct approaches- such as timing a falling ball and working our the acceleration due to gravity using the equations of motion.
. Indirect approaches- such as measuring the time taken for a pendulum to complete a full swing, because the motion of a pendulum is dependent on the value of g.
What makes up stopping distance?
Total stopping distance = thinking distance + braking distance
Factors that increase thinking distance
.Higher speed
.Tiredness
.Alcohol and drugs
.Distractions
.Age of driver
Factors affecting braking distance
.Higher speed
.Poor road conditions (icy or wet)
.Poor condition of brakes
.Poor conditions of tyres
.Mass of car
Equation for thinking distance
Thinking distance(m) = reaction time of driver(s) x speed of car(ms-1)
Equation for braking distance
1/2mv^2 = Fd
