Physical Quantities and Vectors Flashcards
-Any number that is used to describe the physical phenomenon quantitatively.
-one that can be measured and consists of a magnitude and unit.
-can be expressed in terms of small number of fundamental quantities, such as mass, distance, time, electric charges and temperature
Physical Quantities
Two types of Physical Quantities
Base Quantities
Derived Quantities
is like the brick – the basic building block of a house
Base Quantity
is like the house that was build up from a collection of bricks (basic quantities)
Derived Quantities
quantities described only by its magnitude and unit
Scalar Quantities
Examples of Scalar Quantities
Distance
Speed
Temperature
quantities described by both magnitude and direction
Vector Quantities
Examples of Vector Quantities
Displacement
Velocity
Acceleration
Force
-Simplest vector quantity
-Denotes the change in position of an object
in space. Represented by an arrow from the start point to the end point.
-Numerically, it is expressed as distance between points A & B, with an appropriate unit, and a direction
-Depends only on the starting and end point
Displacement
T/F: Round trip has zero displacement
True
Two vectors A and B may be defined to be equal if they have the same magnitude and point in the same direction. That is, A = B
Equality of a vector
If they have the same directions, then it is called __________-
Parallel vectors
If two vectors have opposite direction whether their magnitudes are the same or not, it is called as ______________
Antiparallel vectors
What is the graphical method for vector addition where the second vector is drawn with its tail starting from the tip of the first vector?
Head to Tail/ Polygon Method
What graphical method is used to find the resultant vector of two vectors when they are both drawn with their tails at the same point, and the resultant vector is the diagonal of a parallelogram formed by the two vectors as adjacent sides?
Parallelogram
a scalar quantity that refers to
“how much ground an object has
covered” during its motion
* Unit: meter (m)
distance
- a vector quantity that refers to “how far
out of place the object is” - Unit: meter (m)
Displacement
a scalar quantity which tells us how fast a body is moving.
* defined as the rate of change of distance with respect to time.
- Unit: meter per second (m/s)
Speed
- a vector quantity which tells us how
fast a body is moving and in what direction. - Unit: meter per second (m/s)
Velocity
occurs when an object moves equal displacements in each successive equal unit in time.
Motion with constant velocity
how fast or how slow something is moving
– how fast or how slow the displacement change
Velocity
how fast or how slow the velocity changes
– change in magnitude of velocity or a change in direction
Acceleration
is the limit of the average acceleration as the time interval approaches zero
Instantaneous acceleration
If x-velocity is positive and increasing (getting more positive), x-acceleration is?
positive: particle is moving in +x-direction and speeding up
