Measuring Motion Flashcards
(28 cards)
What does a driver with a slow reaction rate do to the stopping distance of a car?
Lengthens the stopping distance
What can a ticker timer strip be used to measure?
The speed of an object
How is average speed calculated?
Distance travelled divided by time taken
How do you convert from km/hr to m/s?
Divide by 3.6
How do you convert from m/s to km/hr
Multiply by 3.6
What must an object travelling at constant speed do?
Travel the same distance in the same time
How is time calculated using distance and average speed?
Distance travelled divided by average speed
How is distance calculated?
Average speed multiplied by time
What factors may affect the stopping distance for a car?
Reaction time and road surface
When does an object contain zero acceleration?
When the object is not moving or is moving at constant speed
What is acceleration a measure of and what units is it measured in?
A measure of how much the speed of an object changes every second, measured in metres per second squared
What is acceleration?
An increase in speed, also known as positive acceleration
What is deceleration?
A decrease in speed, also known as negative acceleration
What units are time and velocity measured in?
Seconds and metres per second
How do you calculate the change in velocity?
Final velocity minus initial velocity
How is acceleration calculated using velocity and time?
Change in velocity divided by time
How is time calculated using velocity and acceleration ?
Change in velocity divided by acceleration
How is the change in velocity calculated?
Acceleration multiplied by time
What is Newton’s second law of motion?
A non-zero net force produces acceleration
What are the units of net force, mass and acceleration?
Newtons, kilograms and metres per second squared
How is acceleration calculated using net force and mass?
Net force divided by mass
How is mass calculated?
Net force divided by acceleration
How is net force calculated?
Mass multiplied by acceleration
Why does the booster rocket of a space shuttle produce the same constant force all the time, yet its acceleration increases as time goes by?
The net force is constant and the acceleration is increasing, therefore the mass must be decreasing. Mass decreases as fuel is burnt up, thus the acceleration increases
