Concepts to memorise Flashcards
What is the formula for the change in velocity?
The change in velocity is the final velocity - initial velocity, with direction
You must always start with the final velocity and determine if it is negative or positive based on the question
What is the value for acceleration due to gravity?
9.8 m/s^2
What is the formula for calculating the final speed of an object?
Absolute value of the: Final speed - Initial speed
What is the formula for displacement? What does displacement stand for?
Displacement stands for ‘s’ in physics.
s = ut + 1/2at^2
Displacement = Initial velocity x time+ 1/2 x acceleration x time squared
It can also be calculated by final position - initial position
There are many ways to solve displacement and it depends on the type of question and what the question gives you.
What is acceleration by definition?
Acceleration is a vector quantity. It is defined as the rate at which an object changes its velocity. Acceleration also has direction in its answer.
What is the similarities and differences between Instantaneous speed and Average Speed?
Instantaneous speed is the speed of an object at a particular point in time. However, Average speed is the overall speed of an object, where the total distance travelled is divided by the total time taken. Both are scalar quantities since they deal with only magnitude.
What does the speedometer of a car indicate? (What type of speed is it exaclty?)
a SPEEDOMETER indicates the instantaneous speed of a car. Therefore, it shows you the speed of the car at a particular moment in time.
What is the formula for the ‘average velocity?’
Average velocity = change in displacement / change in time
because velocity = displacement / time or s/t
IT COULD ALSO BE: V + U / 2
What is the formula for final velocity?
Final velocity (which stands for ‘v’) = Initial velocity (u) + acceleration x time
v = u + at
What is the formula v^2 = u^2 + 2as? (what does it stand for?)
v = Final velocity u = initial velocity a = acceleration s = displacement
What are the 7 main formulas needed for problem solving in physics?
a = v-u / t where acceleration = change in velocity / change in time
s = ut + 1/2 x a x t^2 where displacement = initial velocity x time + 1/2 x acceleration x time squared
v = u + at where final velocity = initial velocity + acceleration x time
v^2 = u^2 + 2as where final velocity squared = initial velocity squared + 2 x acceleration x displacement
v(av) = u + v / t = s / t where average velocity equals to displacement over time or addition of final and initial velocities
divided by time between the two
Speed = Distance / Time
v = s / t where final velocity = displacement over time
What does ‘v’ stand for in physics?
v stands for FINAL VELOCITY. u stands for initial velocity
If an object changes directions, is it accelerating? Why?
Yes, changing directions means that the object is accelerating.
Acceleration is a vector quantity and it is defined as a change in velocity over time. So if the speed remains the same, if an object changes direction it is still accelerating.
When is the equation v^2 = u^2 +2as most useful during a physics problem?
Final velocity squared = Initial velocity squared + 2 x acceleration x displacement
This equation is most useful when the problem does not give you the TIME. When there is no time involved in the question, it is most likely that this formula would be useful.
Always determine if the question is asking for a scalar quantity or a vector quantity. Always put DIRECTION WHEN NEEDED, and REMEMBER TO TURN NEGATIVE VALUES BACK TO DIRECTIONS WHEN USING SIGN CONVENTIONS;
YES
