2025 predicted primrose

• An experiment to determine the magnetic field pattern around a bar magnet 


  1 way:

  place a magnet on a sheet of paper and position small magnetic compasses around the magnet. Plot the directions that the compass needles point

  2 way:

  Place a piece of paper on top of the magnet and sprinkle with iron filings. Tap the paper.
• Explain how the behaviour of a magnetic compass is related to evidence that the core of the Earth must be magnetic

  When not near a magnet, the needle of a compass (north arrow)will always point towards the geographic north pole/magnetic south pole. Therefore,the core must be made of a magnetic material.
• experiment improved -how??????

  -Measure the width of the card

  -Repeat and take an average

  -Use an alternative method, measuring distance without the presence of a card
• Electromagnetic waves can be used

  for communication using satellites that orbit the Earth
• A transmitter can send a signal to an orbiting satellite

  which can send then send that signal to a receiver
• satellites have

  circular orbits
• Satellite orbits the Earth, it's a velocity change. Speed remains constant. explain why he velocity changes, while the speed remains constant

  The motion is constantly changing direction. As velocity is a vector, changing the direction changes the velocity.
• Suggest why microwaves are used for communication

  They pass easily through the atmosphere
• What is meant by terminal velocity

  The maximum speed of an object.

  Reached when the forces are balanced/resultant force=0
• newtons first law

  if the resultant force on a stationary object is zero-the object will remain stationary

  -if the resultant force on a moving object is zero-the object will continue moving in the same direction with he same speed.
• Transverse waves-the oscillations/vibrations are perpendicular to the direction of the energy transfer

  Longitudinal waves-the oscillations/vibrations are parallel to the direction of the energy transfer
• property of visible light

  longest wavelength-Red

  highest frequency-Violet
• elastic deformation-

  The object returns to its original shape after the forces are removed.
• Inelastic deformation

  The object does not return to its original shape after the forces are removed.
• elastic potential energy unit

  Joules/J
• Lubricant called graphite is used, why?

  -reduce friction

  • decrease the work done
• Some workplaces, where employees are exposed to electromagnetic waves, need to complete risk assessments to evaluate the risk to their employees.

  c) Use your knowledge of electromagnetic waves to discuss the factors that must be considered when evaluating the risks of exposure to electromagnetic waves and any potential dangers of exposure.[6 marks]

  • The effect of radiation is dependent on the type of radiation.
  • The effect of radiation is also dependent on the size of the radiation dose.
  • Radiation dose is a measure of the risk of harm that can result from an exposure of the body to radiation.
  • Of the electromagnetic waves, UV, X-rays and gamma rays can have hazardous effects.
  • Ultraviolet waves can cause premature skin aging / cataracts / increased risk of skin cancer / other valid points.
  • X-rays and gamma rays are ionising radiation.
  • X-rays and gamma rays can cause mutation of genes and cancer.