Module 5 Extended Responses
Different Trajectories in Projectile Motion due to Air Resistance
Effects without Air Resistance
● The projectile travels with a constant vertical acceleration due to gravity
● The projectile has zero horizontal acceleration.
● There is equal time between reaching the peak of its height and falling back to the ground,
resulting in a parabolic path
Effects of Air Resistance
● With air resistance, there are three impacts on the projectile
○ The greater the velocity of the projectile, the greater the drag force
○ The more streamlined the projectile, the less the effects of the drag force
○ The higher the air density, the greater the drag force
● Thus, the projectile with air resistance takes longer to fall as its horizontal velocity decreases
and its descent is retarded by the drag force of air.
,Sliding Off a Banked Track
● A vehicle travelling at the design speed requires no friction to turn
● If the speed is increased past the design speed, a larger centripetal force will be needed to turn
● The horizontal component of the normal force will be less than the required centripetal force
● As there is no friction, the car slides off
Work Done in Circular Motion
● No work is done in circular motion
● The displacement and force vectors are perpendicular
● Using W=Fscosθ, this results in Fscos90 = 0
Geostationary Satellites
Characteristics of Geostationary Satellites
● The period of a geostationary satellite is 24 hours, equal to Earth’s orbital period
● Geostationary satellites are located on the equator
● Travel eastwards in the direction of Earth’s orbit
● Travel in a circular orbit
● Remains at the same point above the Earth’s surface
Applications of Geostationary Satellites
● Communications and Broadcasting
● Global Positioning System (GPS)
● Weather and Climate Monitoring
, Module 6 Extended Responses
Contribution of Maxwell to Electromagnetism and Subsequent Evidence
Maxwell’s Contributions
● Unified Electricity and Magnetism
○ Maxwell proposed that an accelerating charge would create an oscillating electric field,
giving rise to a perpendicular magnetic field. This would induce another electric field.
○ Mutually propagating electric and magnetic fields that unified both fields of physics
○ Can use a diagram to describe this form of propagation
● Predicted speed of light was constant
○ Maxwell described light to be an EM wave
○ His equations predicted that the speed of light was a constant value for all light
● Predicted forms of EM outside visible light
○ Using the wave equation, Maxwell predicted a whole range of EM waves
○ Predicted the existence of radio waves up to gamma rays
Experimental Evidence to Support Contributions
● Spark-Gap to produce Radio Waves
○ Hertz developed an apparatus to demonstrate the theory of EM wave propagation
○ An accelerating electric charge from one coil would induce an electrical spark to jump
across an air gap to another coil tuned as the same frequency
○ Discovery of radio waves
● Speed of Radio Waves
○ Hertz used the interference of radio waves to calculate their speed
○ Found that the speed of radio waves was the same as the speed of light
● Existence of other EM waves
○ Other EM waves from microwaves to gamma rays were then discovered
○ Applied in practical uses such as communications and medical imagery
Different Trajectories in Projectile Motion due to Air Resistance
Effects without Air Resistance
● The projectile travels with a constant vertical acceleration due to gravity
● The projectile has zero horizontal acceleration.
● There is equal time between reaching the peak of its height and falling back to the ground,
resulting in a parabolic path
Effects of Air Resistance
● With air resistance, there are three impacts on the projectile
○ The greater the velocity of the projectile, the greater the drag force
○ The more streamlined the projectile, the less the effects of the drag force
○ The higher the air density, the greater the drag force
● Thus, the projectile with air resistance takes longer to fall as its horizontal velocity decreases
and its descent is retarded by the drag force of air.
,Sliding Off a Banked Track
● A vehicle travelling at the design speed requires no friction to turn
● If the speed is increased past the design speed, a larger centripetal force will be needed to turn
● The horizontal component of the normal force will be less than the required centripetal force
● As there is no friction, the car slides off
Work Done in Circular Motion
● No work is done in circular motion
● The displacement and force vectors are perpendicular
● Using W=Fscosθ, this results in Fscos90 = 0
Geostationary Satellites
Characteristics of Geostationary Satellites
● The period of a geostationary satellite is 24 hours, equal to Earth’s orbital period
● Geostationary satellites are located on the equator
● Travel eastwards in the direction of Earth’s orbit
● Travel in a circular orbit
● Remains at the same point above the Earth’s surface
Applications of Geostationary Satellites
● Communications and Broadcasting
● Global Positioning System (GPS)
● Weather and Climate Monitoring
, Module 6 Extended Responses
Contribution of Maxwell to Electromagnetism and Subsequent Evidence
Maxwell’s Contributions
● Unified Electricity and Magnetism
○ Maxwell proposed that an accelerating charge would create an oscillating electric field,
giving rise to a perpendicular magnetic field. This would induce another electric field.
○ Mutually propagating electric and magnetic fields that unified both fields of physics
○ Can use a diagram to describe this form of propagation
● Predicted speed of light was constant
○ Maxwell described light to be an EM wave
○ His equations predicted that the speed of light was a constant value for all light
● Predicted forms of EM outside visible light
○ Using the wave equation, Maxwell predicted a whole range of EM waves
○ Predicted the existence of radio waves up to gamma rays
Experimental Evidence to Support Contributions
● Spark-Gap to produce Radio Waves
○ Hertz developed an apparatus to demonstrate the theory of EM wave propagation
○ An accelerating electric charge from one coil would induce an electrical spark to jump
across an air gap to another coil tuned as the same frequency
○ Discovery of radio waves
● Speed of Radio Waves
○ Hertz used the interference of radio waves to calculate their speed
○ Found that the speed of radio waves was the same as the speed of light
● Existence of other EM waves
○ Other EM waves from microwaves to gamma rays were then discovered
○ Applied in practical uses such as communications and medical imagery
