define a force. what unit are forces measured in? how can we measure a force?
TRANSCRIPT
Balanced and unbalanced forces
Define a force.
What unit are forces measured in?
How can we measure a force?
Balanced and unbalanced forces
Objectives
Know what balanced and unbalanced forces are.
Understand the effect if forces are balanced and
unbalanced.
Outcomes
(4) Draw diagrams to represent balanced and unbalanced
forces.
(5) Calculate resultant forces.
(6) Explain the effects of balanced and unbalanced forces
on objects.
Key terms: Force, Newton, balanced, unbalanced, resultant.
Balanced Forces produce
NO change in Movement
Unbalanced Forces
Change the Speed and or
Direction of Moving Objects
Balanced and Unbalanced Forces
The forces on the person are balanced
The floor pushes upward on the person
Weight pulls downwards on the person
Greater Force
Smaller Force
DA B CResistance
Weight
Weight
Resistance
Weight
Which diagram is correct?
Why?
Resistance
THRUSTDRAG & FRICTION
What is the bicycle doing?
C
A
B
D
Not moving
Slowing down
Speeding up
Moving at constant speed
If the swimmer is floating, which diagram is correct?
WEIGHT WEIGHT WEIGHT WEIGHT
TURBULENCEDRAGUPTHRUSTRESISTANCE
BA E D
WEIGHT
DRAG
B
A
C
D
Hovering in the air
Falling at constant speed
Slowing down
Speeding up (plunging to a horrible death)
What is the parachutist doing?
Which diagram shows a balloon floating at a constant height?
WEIGHT
UPTHRUST
WEIGHT
UPTHRUST
WEIGHT
UPTHRUST
WEIGHT
DRAG
DA B C
THRUST THRUST
THRUST THRUST
DRAG & FRICTION
DRAG & FRICTION
DRAG & FRICTION
DRAG & FRICTION
Which car is slowing down?
C
A B
D
TITANIC
WHITE STAR LINE
Which statement is not correct?
The Titanic is sinking because the upthrust on it is less than its weight
The iceberg is floating because the upthrust on it is equal to its weight
The Titanic is sinking because there is less upthrust on it than there is on the iceberg
The Titanic weighs less than the iceberg
B
A
C
D
WEIGHT
WEIGHT
UPTHRUST
UPTHRUST
Copy the diagrams below, adding arrows to show ALL the forces acting on the object indicated
A stone in a beaker of water
An ice skater moving at constant speed
A plane accelerating forwards in the air
WEIGHT
RESISTANCE
UPTHRUST
WEIGHT
RESISTANCE
THRUSTFRICTION & DRAG
DRAG THRUST
WEIGHT
LIFT
Balanced and unbalanced forces
Task
Answer the questions on the worksheet.
Outcomes
(4) Draw diagrams to represent balanced and unbalanced
forces.
(5) Calculate resultant forces.
(6) Explain the effects of balanced and unbalanced forces
on objects.
Key terms: Force, Newton, balanced, unbalanced, resultant.
Balanced and unbalanced forces
Peer review
Exchange sheets.
Mark the other persons sheet, give them a total
mark.
Clearly write who has marked the work.
Outcomes
(4) Draw diagrams to represent balanced and unbalanced
forces.
(5) Calculate resultant forces.
(6) Explain the effects of balanced and unbalanced forces
on objects.
Key terms: Force, Newton, balanced, unbalanced, resultant.
In which direction will these stationary objects move?
Will it move?
ForceNewton Newton
MeterFriction
Density
Balanced
Unbalanced
GravityWeight
Mass
Kilogram
Speed Metres persecond
Volume
Upthrust