Physics

Base Quantities

The basic quantities that are used to define all quantities of the system. Length, mass, and time.

Derived Quantities

Quantities that can be expressed as algebraic combinations of base quantities.

SI standard of time is based on what

Vibration of atoms of Cesium-133

Is there an SI base unit for area

Area can be expressed in terms of square meters

SI standard of length is based on what

The speed of light

The SI base units

Meter (L), Kilogram (M), Second ( T)

Vector Quantity

A quantity with both magnitude (how large) and direction to be specified

Scalar Quantity

A quantity that only needs magnitude to be specified.

Representation of Vectors

A statement providing its magnitude and direction
Using a variable name with a little arrow

Representing a vector graphically

Vector A and B lie in the x-y plane. A = B if:

A_x = B_x and A_y = B_y

Let A = 2î + 6j - 3k and B = 4î + 2j + k. How is A . B found?

Combine like terms.

The value of k x(j x î)

0

The diagram above shows a velocity-time graph for a car moving in a straight line. At point Q the car must be:

moving with zero acceleration

The diagram represents the straight line motion of a car.

The car accelerates at 6 m/s² for the first 2 s

The position-time graph of an object is a straight line with a positive slope. The object has

constant velocity

Position

Its location with respect to the origin of the reference

Initial

When we start observing the object

Final

When we stopped observing the object

Equation for average speed

Distance traveled/ time of travel

Displacement

Change in position

Average Velocity

Displacement/time (final - initial)

Unit of acceleration

Velocity (m/s) divided by time (s)