Kaplan Physics and Math: Chapter 1 - Kinematics and Dynamics

The content in this chapter should be relevant to about 6% of all questions about physics on the MCAT.

What are the basic units of the FPS system?

Foot (ft) for length, pound (lb) for weight, and second (s) for time.

What are the base units of the MKS system?

Meters, kilograms, and seconds.

What is the SI base unit for electric current?

Ampère (A) — equivalent to one coulomb per second.

What is the SI base unit for amount of substance?

Mole (mol).

What is the SI base unit for temperature?

Kelvin (K)

Whatis the SI base unit for length?

meter (m)

What is the SI base unit for mass?

kilogram (kg)

what is the SI base unit for time?

seconds (s)

What is the SI base unit for luminous intensity?

Candela (cd)

What are base units?

Base units are the standard units around which the system itself is designed

What are derived units?

Derived units are created by associating base units with each other. For example, the newton—a unit of force—is derived from kilograms, meters, and seconds:

What are vectors?

A number with both magnitude and direction.

What are some examples of vector quantities?

Displacement, velocity, acceleration, and force.

What is a scalar?

A number that has magnitude only and no direction.

What are some examples of scalar quantities?

Distance, speed, energy, pressure, and mass.

What’s the key difference between a vector and a scalar?

Vectors have direction; scalars do not.

How are vectors typically represented visually?

By arrows — the direction of the arrow shows the vector’s direction, and the length represents its magnitude.

What is the sum or difference of two or more vectors called?

The resultant of the vectors.

What is the tip-to-tail method of vector addition?

Place the tail of one vector (B) at the tip of another (A) without changing their magnitude or direction.
The resultant (A + B) is drawn from the tail of A to the tip of B.

In the tip-to-tail method, what must the lengths of the arrows be proportional to?

The magnitudes of the vectors.

How are vector components typically defined?

As horizontal (x) and vertical (y) components.
Sometimes as parallel (‖) and perpendicular (⊥) to a surface (e.g., inclined plane)

How do you find the magnitude of a vector from its components?

V = sqrt (V_x²+V_y²)