Forces and motion - Forces, movement, shape and momentum Flashcards
What are the possible effects of forces on an object
Changes in Speed
Changes in Shape
Changes in Direction
What are two different type of force
Gravitational
Electrostatic
What are vector quantities
Include both magnitude and an associated direction
e.g: Force, 20 newtons (N) to the left
What are scalar quantities
Include only a magnitude or size
e.g: mass 5 kilograms
What type of quantity is a force
A vector quantity
Know how to calculate a resultant force
’’’’’’’’'’6N 4N
e.g: ——> O <———
Resultant force = 6N - 4N = 2N
What is friction
A force that opposes motion
What is the equation linking weight, mass and gravitational field strength
weight = mass x GFS
W = m x g
Know the relationship between unbalanced force, mass and acceleration
Force = mass x acceleration
F = m x a
What makes up the stopping distance of a vehicle
The thinking distance
+
The braking distance
What are factors that affect a vehicles stopping time
- Speed
- Mass
- Road condition
- Rea
What factors affect the reaction time of a driver
- Sober or not
- Tired or not
- Age (older = less reaction time)
What are the forces acting on a falling object
1) At the start the object accelerates downwards due to the force of gravity
2) As the object’s speed increases, frictional forces such as air resistance or drag increase.
3) At terminal velocity, the weight of the object due to gravity is balanced by the frictional forces and the resultant force is zero.
Practical: Investigate how extension varies with applied force for helical springs, metal wires and rubber bands
https://www.savemyexams.com/igcse/physics/edexcel/19/revision-notes/1-forces-and-motion/1-2-forces-movement-and-changing-shape/1-2-8-core-practical-investigating-force-and-extension/
What is Hooke’s law
a law stating that the strain in a solid is proportional to the applied stress within the elastic limit of that solid
