# Physics, Chemistry & earth/space Flashcards

What is a physical quantity?

Physical quantities are quantity in physics that can be measured and given a number

what is a scalar quantity?

quantity that has size but not direction

what is a vector quantity?

is a quantity that has size and direction

what is distance?

- Is how far an object travels in total

- Is a scalar quantity measured in meters

what is displacement?

- is the straight-line distance between the starting and finishing points
- is a vector quantity, and is also measured in meters

what is speed?

How fast something is moving. Uses distance for calculating it. It is a Scalar Quantity

what is velocity?

How fast something is moving with a direction. Uses displacement for calculating it. It is a Vector Quantity

what is acceleration?

the rate of change of velocity. Is a Vector value. Given the unit m s-2

how do you identify acceleration?

- If an object is changing speed or direction then it is accelerating
- Also, objects with unbalanced forces applied are accelerating

what is newtons 1st law?

Law of inertia - An object at rest tends to remain at rest; an object in motion tends to remain in motion at constant speed along a straight-line path

what is newtons 2nd law?

When a force acts on an object, the object will accelerate. The acceleration is proportional to the net force and inversely proportional to the mass

what is newtons 3rd law?

Law of action/reaction - Whenever one object exerts a force on a second object, the second object exerts an equal and opposite reaction on the first

what is the law of conservation of energy?

Energy cannot be created or destroyed, only transferred or transformed

what is the relationship between distance from sun and temperature?

as the distance from the sun increases the average temperature decreases

what is the difference in temperature of objects with atmosphere compared to those without?

the objects with an atmosphere have a hotter average temperature than the objects without