electromagnetism

• What does the Earth act like in terms of magnetism?

  A big bar magnet
• What do magnetic field lines represent?

  The direction from north to south
• What is the direction of magnetic field lines?

  From north to south
• What happens to a free north pole in a magnetic field?

  It follows the magnetic field lines
• What indicates a uniform magnetic field?

  Equally spaced parallel lines
• What is the field pattern of two opposing poles?

  Similar to a uniform field
• What shape do magnetic field lines take around a current-carrying wire?

  Concentric circles
• What does a circle with a cross indicate in magnetic field notation?

  Current going into the page
• What does a circle with a dot indicate in magnetic field notation?

  Current coming out of the page
• What is the right-hand grip rule used for?

  To determine magnetic field direction
• How do you apply the right-hand grip rule?

  Grip the wire with your right hand
• What happens to the magnetic field direction if the current direction is reversed?

  The magnetic field direction also reverses
• What is the direction of the magnetic field at point A if the current is upwards?

  Out of the screen
• What is the direction of the magnetic field at point B if the current is upwards?

  Into the screen
• What is the magnetic field inside a solenoid assumed to be?

  Uniform
• What determines the direction of the north and south poles in a solenoid?

  The direction of the current
• What happens to the magnetic poles if the current direction in a solenoid switches?

  The poles will also be reversed
• What is the formula for the magnetic force on a current-carrying wire?

  f = BIL sin θ
• What does B represent in the magnetic force equation?

  Magnetic flux density
• What does I represent in the magnetic force equation?

  Current in amps
• What does L represent in the magnetic force equation?

  Length of the wire in meters
• When is the magnetic force maximum according to the equation f = BIL sin θ?

  When θ is 90 degrees
• When is the magnetic force zero according to the equation f = BIL sin θ?

  When θ is 0 or 180 degrees
• What does Fleming's left-hand rule help determine?

  The direction of the magnetic force
• How do you apply Fleming's left-hand rule?

  Use your left hand with fingers positioned
• What does the thumb represent in Fleming's left-hand rule?

  The direction of the force
• What does the first finger represent in Fleming's left-hand rule?

  The direction of the magnetic field
• What does the second finger represent in Fleming's left-hand rule?

  The direction of the current
• What happens to a positive charge in a magnetic field?

  It curves due to centripetal force
• What is the relationship between magnetic force and centripetal force for a charged particle?

  They are equal when moving in a circle
• What is the formula for the radius of curvature of a charged particle in a magnetic field?

  r = mv / qB
• What is magnetic flux defined as?

  The product of magnetic flux density and area
• What is the formula for magnetic flux?

  Φ = B A cos θ
• What does θ represent in the magnetic flux formula?

  The angle between field lines and normal
• What is a common mistake regarding the angle θ in magnetic flux?

  Confusing it with the angle of the field lines
• What is the component of magnetic flux perpendicular to an area called?

  Magnetic flux density
• How is the magnetic flux defined?

  As the product of magnetic flux density and area
• What is the formula for magnetic flux?

  φ = B * A * cos(θ)
• What does θ represent in the magnetic flux equation?

  The angle between the field lines and the normal
• When is the magnetic flux at its maximum?

  When the field is perpendicular to the area