Physics Basics Flashcards
What is Distance?
Distance is how far an object has travelled
What is displacement?
Displacement is the overall change in direction and position of an object from its starting point
What is a scalar quantity? Give 5 examples
A scalar quantity has magnitude only. It DOES NOT have direction or any information regarding direction.
Examples of scalar quantities include: Temperature, Pressure, Time, Distance, Volume, Speed and Mass
Why is temperature a scalar quantity?
A scalar quantity is just a value, with only the magnitude. There is no direction in temperature, making it a scalar quantity. Temperature is just a value and it is there as a whole, rather than in one specfic direction
What is a vector quantity?
A vector quantity has magnitude AND direction
What are 5 examples of a vector quantity?
Velocity, Displacement, Force, Acceleration and Magnetic Field
ALSO ‘Acceleration due to gravity’
What is the SI unit for distance and displacement?
Meters (M)
What is velocity? How do you find it? What is the formula?
Velocity is the speed of something in a particular direction
Velocity = S/T (Where S stands for displacement)
Therefore, velocity = Displacement / Time
What is a position time graph?
A position-time graph is also known as a displacement time graph. It depicts the motion of an object and shows how far an object has travelled from its original starting point.
The vertical axis is always labelled ‘Position’ and the horizontal axis is always labelled ‘Time’
Define speed. What is the SI unit
Speed is a measure of how fast a moving object is travelling. The SI unit is meters / second
*Always convert km or mm to meters and hrs or days to seconds, unless the question states otherwise
The rate at which an object travels
What is the formula for average speed, distance and Time?
Average Speed = Distance / Time
Distance = Speed x Time
Time = Distance / Speed
How is velocity determined from a position-time graph?
By the Gradient/Slope
What is acceleration?
Acceleration is the rate of change of speed
Acceleration is the rate at which an object changes its velocity
Is acceleration a scalar or vector quantity?
Acceleration is a vector quantity because it has both magnitude and direction. Since it is related to velocity and velocity is the speed of something in a particular direction, acceleration must be vector
What is another word for deceleration
Negative acceleration
What is the symbol for ‘acceleration due to gravity’
What is acceleration due to gravity?
What is the SI unit?
g
Acceleration due to gravity is the acceleration gained by an object due to gravitational force
M/S^2 (meter per second squared)
What is the formula for acceleration
Acceleration = change in distance / change in time
Acceleration = The change in velocity / Change in Time
Acceleration = v - u / t
What is a speed time graph? What does it indicate?
A speed time graph represents an object’s speed graphically. It is also known as a velocity time graph
Vertical axis is speed in meters per second
Horizontal Axis is Time in seconds
What does the area underneath a speed time graph indicate?
The area underneath a speed time graph, indicates the total distance that an object has travelled
What is instantaneous speed?
The instantaneous speed is the speed of an object at a particular point in time
what is the si unit for acceleration? Why is it like that?
Meters per second squared (m/s^2)
This is because acceleration is the ‘change in velocity / change in time’. Since velocity = Displacement / time and the si unit for velocity is meters per second, acceleration is velocity divided by time. Therefore, it is m/s divided by seconds –> making it m/s^2
What is a jerk?
A jerk is the rate of change of the acceleration
Jerk = Change in acceleration / Change in time
How can you convert km/h to m/s ?
What is the formula, other than solving km to m and hrs to seconds individually
m/s x 3.6 = Km/h, multiply by 3.6
Km/h / 3.6 = m/s, divide by 3.6
What is the formula for average speed?
Average speed = Distance / Change in Time
In what situation will the object’s velocity be equal to the object’s speed?
The object’s speed and velocity will be equal when an object travels in a straight line, without changing its direction
Speed cannot be negative. True/False
True, speed can NEVER be negative
How do you calculate the change in speed of an object?
How do you calculate the change in velocity of an object?
Change in speed is ALWAYS POSITIVE. Change in speed = Absolute value of Final speed - Initial speed (This is because if the final speed is smaller than the initial speed, then the result would be negative. Thus, finding the absolute value is essential when calculating the change in speed.
Since velocity is speed WITH direction, the change in velocity is calculated through negative and positive numbers based on the direction and follows the formula: Change in velocity = Final velocity - Initial Velocity
