TOPIC 2 - FORCES AND MOTIONS Flashcards
What is a scalar quantity?
Has magnitude (size) but no direction
What is a vector quantity?
Has magnitude and direction
What is acceleration?
The change in velocity
What is acceleration in free fall on Earth?
10m/s
Speed equation
distance/time
Acceleration equation
change in v/time
Equation linking acceleration and distance
v^2-u^2=2 x acceleration x distance
What is Newton’s 1st law?
Where the resultant force is 0, the body moves at constant velocity or is at rest. When there is a resultant force, the speed and or direction of the body changes (accelerates)
What is Newton’s 2nd law?
Acceleration depends on
1.the size of the force (the larger the force, the larger the accel.)
2.the mass of the object (more mass = less accel.)
F=ma, hence acceleration is inversely proportional to mass
What is Newton’s 3rd law?
When 2 objects interact, action-reaction forces act (they are same size and same type of force but opposite direction). But forces have different effects if objects are different mass.
What is the different between mass and weight?
Mass is quantity of matter, weight is a measure of pull of gravity (a force).
Equation for weight
weight(N) = mass(kg) x gravitationa forcel(N/kg)
What is centripetal force?
any force is causing object to move in a circle, acting towards a circle and causes acceleration
What affects centripetal force?
- Radius of circle (smaller radius=more acceleration)
- Speed of object (more speed=more acceleration)
- Mass (more massive=needs larger force)
What is inertial mass?
how difficult it is to change velocity of an object. mass=f/a.
