# Unit 1 Revision Checklist

• Published on
14-May-2017

• View
218

4

Embed Size (px)

Transcript

• 1

Unit 1: Check List Mechanics Motion:

Understand the difference between scalar quantities and vector quantities

Understand how to add vectors using trigonometry and the parallelogram rule

Understand that a vector quantity at an angle can be split into its horizontal and vertical components

Understand and know the differences and definitions for

Distance and displacement

Speed and velocity - and differentiate between instantaneous and average velocities

Force and acceleration

Know how to draw distance/displacement time, velocity time or acceleration time graphs

What is the difference between UNIFORM velocity and CONSTANT velocity

Know the /displacement time, velocity time or acceleration time graphs for objects that are:

Stationary

Moving with constant velocity

Accelerating uniformly

Accelerating non uniformly

Decelerating uniformly

Know what the gradient and area under the graphs mean for the different types of graphs mentioned above

Know and learn the four main equations of motion

Understand that the four main equations of motion are only applicable when acceleration is constant

Understand what is free fall and the condition for free fall

Know what is a projectile and its trajectory

Know the different types of projectile trajectories : vertical, horizontal and angular

Know which equations to use to calculate the time taken, the vertical velocity and horizontal velocity and distance

Explain angular projectiles follow a parabolic path

Explain why an object projected horizontally and dropped vertically simultaneously will reach ground at the same instant

• 2

Unit 1: Check List Mechanics Forces:

Understand the different types of forces, e.g., contact forces, non- contact forces, electromagnetic f0rces, etc.

State and explain Newtons First Law of Motion

Explain what is equilibrium and relate Newtons first law with bodies in equilibrium

Understand the concept of inertia, mass and weight

Understand how the centre of gravity of a body affects the stability of a body in equilibrium

Understand how to draw vector diagrams of objects in equilibrium

Understand how to draw free body force diagrams

State and explain Newtons Second Law of Motion

Know the effect of change in force acting on a fixed mass

Know the effect of change in mass on the acceleration produced by a fixed force

Understand that a resultant force is needed for an acceleration to occur and that they are proportional to each other

Explain the concept of the unit of newton using the equation F = ma

Remember that the acceleration is always in the direction of the resultant force

Explain how Newtons Second Law includes the First Law

Calculate the resultant force on multi-body systems

Explain the concept of apparent weightlessness

State and explain Newtons Third Law of Motion

Understand that forces come in pairs

Remember the conditions for two forces to be a Newtons Third Law pair force

Understand how to recognize third law pair forces

Understand the connection between Newtons third law and equilibrium

Mechanics Mechanics in the Real World:

Explain the motion of a bouncing ball with appropriate graphs

Draw velocity time graph for a person falling under free fall and then opening the parachute

Explain the change in weight of bodies inside a lift

Understand what forces act on a vehicle to make it move and keep it moving

Understand the physics behind the safety of vehicles e.g. use of crumple zones, thinking distance, braking distance, etc.

Show how forces act on sports people, e.g. bungee jumpers, rock climber, parachutist in free fall

• 3

Unit 1: Check List Mechanics Work, energy and power:

Understand the difference between work and energy with respect to their definitions

Understand the relationship between work and energy

Explain the definition of a joule

Define potential energy (gravitational and elastic) and kinetic energy

Derive the formula for kinetic energy

Understand that all forms of energy can be described in terms of potential energy and kinetic energy

Understand that gravitational potential energy is directly converted to kinetic energy during free fall

Understand the concept of internal energy

Understand and explain the principle of conservation of energy

Learn how to draw Sankey diagrams

Calculate efficiency

Define what is power

Link power with motion and derive the corresponding formula

Materials Fluids:

Define density and pressure

Derive the equation of pressure of a fluid in terms of height and density

Explain how upthrust equals the weight of the fluid displaced

Explain how objects float

Explain why a ship floats while a brick sinks

Define stream lines

Define laminar flow and turbulent flow

Learn the real world applications of laminar flow and turbulent flow e.g. designs of aeroplanes, sports cars, etc.

Define viscosity

Understand that viscosity of a fluid depends on the temperature of the fluid

Learn the unit for the coefficient for viscosity

Understand that viscous drag acts on an object moving through fluids

Learn that the viscous drag force is given by Stokes law

Remember the conditions for Stokes law to be valid

Understand that an object achieves terminal velocity when the resultant force on the object is zero

Draw the free body force diagram for a sphere falling down or moving up in a fluid and write down relevant equations

• 4

Unit 1: Check List Materials Solid Materials:

Define the types of materials: rigid, elastic and plastic

Define elastic and plastic deformation

Define the different properties of materials: hardness, toughness, stiffness, brittle, malleable, ductile, etc.

Define elastic and plastic behaviour of a solid

Define Hookes law

Explain the different parts of the graph of a spring being stretched beyond its elastic limit

Define elastic limit, limit of proportionality, yield point, breaking point and hysteresis

Understand the force-extension graph for natural rubber

Learn the different force-extension graphs for different types of metal wires

Define elastic strain energy and how to calculate it form a force-extension graph

Define stress, strain and Young modulus

Define tensile and compressive stress and strain

Understand the difference between stiffness and Young modulus

Understand the concept of necking

Explain a given stress-strain graph

Understand that the gradient and area of a stress-strain graph gives the Young modulus and energy density respectively

Define yield stress, UTS and breaking point

Learn the different stress-strain graphs for rubber, glass, copper wire, wood, iron, etc