Linear Motion Flashcards
Distance
The total length of the path traveled by an object, regardless of direction. It’s a scalar quantity (only magnitude, no direction).
Displacement
The shortest straight-line distance between the starting and ending points of an object’s path, with direction. It’s a vector quantity.
Speed
The rate at which an object covers distance. It’s calculated as distance divided by time and is a scalar quantity (e.g., 50 m/s).
Accerelation
The rate of change of velocity per unit time. It indicates how quickly an object’s speed or direction changes and is a vector quantity.
Velocity
The rate of change of displacement per unit time, which includes direction. It’s a vector quantity (e.g., 60 m/s north).
SI Unit for Time
The second (s) is the base unit for measuring time in the International System of Units (SI).
SI Unit for Displacement
Meter (m), representing the distance in a specific direction.
SI Unit for Speed
Meters per second (m/s), showing how many meters an object travels in one second.
SI Unit for Velocity
Meters per second (m/s), including both magnitude and direction of motion.
SI Unit for Acceleration
Meters per second squared (m/s²), representing the change in velocity per second.
How to convert between m / s to km / h
Multiply by 3.6. (Example: 10 m/s = 10 × 3.6 = 36 km/h).
How to convert from km / h to m / s
Divide by 3.6. (Example: 36 km/h = 36 ÷ 3.6 = 10 m/s).
Define a Vector Quantity
A quantity that has both magnitude and direction (e.g., force, velocity, displacement).
Define a scalar quantity
A quantity that has only magnitude, with no direction (e.g., distance, speed, time).
Is distance vector or scalar
Scalar
Is displacement vector or scalar
Vector
Is speed vector or scalar
Scalar
Is acceleration vector or scalar
Vector
Is velocity vector or scalar
Vector
Is force vector or scalar
Vector
Is time vector or scalar
Scalar
Compare distance and displacement
Distance is the total path length (scalar), while displacement is the shortest path with direction (vector).
What is acceleration due to gravity
9.8 m /s^2
Compare average speed and average velocity
Average speed is the total distance divided by time (scalar), while average velocity is total displacement divided by time (vector).
SI unit for kinetic energy
Joules (J)
SI unit for Gravitational potential energy
Joule (J)
Formula for Gravitational Energy
GPE = mass (kg) x gravity (9.8) x height (m)
Formula for Kinetic Energy
KE = (1 /2) x m x v^2
Do supergiants create heavier elements?
Hydrogen fusion stops in the core of a supergiant because the hydrogen fuel is depleted. The star then starts fusing helium and heavier elements to release energy and balance the forces of gravity. Fusion of hydrogen can no longer occur because the temperature and pressure in the core are high enough to begin fusing heavier elements like helium, carbon, and oxygen.
How does the process of fusing heavier elements differ between low/medium-mass stars and massive stars (supergiants)?
The process of fusing heavier elements happens in both low/medium-mass stars and massive stars (supergiants), but the range of elements fused and the star’s end of life depend on the star’s mass. Low- and medium-mass stars only fuse elements up to carbon and oxygen, and they end their lives as white dwarfs. In contrast, massive stars (supergiants) can fuse elements all the way up to iron. When the core produces iron, fusion stops, leading to a supernova explosion. This explosion creates even heavier elements, such as gold and uranium, and scatters them into space.
How to calculate displacement on velocity time graph
To calculate displacement from a velocity-time graph, you use the concept that displacement is the area under the graph between the time interval of interest. Here’s how to calculate it:
