GK-Physics Exam Preparation

Flashcards created to review key concepts and details for the GK-Physics exam.

What are the two mandatory questions you must answer in Section A of the GK-Physics exam paper?

Question 1 and Question 2.

What is the purpose of the attached DATA SHEETS during the exam?

To assist with calculations and provide necessary formulas.

What is the direction of the force acting on two parallel current-carrying wires with currents in the same direction?

The wires exert an attractive force on each other.

When the switch in the solenoid circuit is closed, what direction will the suspended magnet move?

The suspended magnet will move TOWARDS the solenoid.

What are three ways to increase the effect on the suspended magnet in the provided solenoid system?

Increase the current, increase the number of turns in the solenoid, or decrease the distance between the solenoid and the magnet.

What is observed about the polarity of end A of the solenoid when a north pole approaches it?

End A becomes a south pole as the north pole approaches.

What type of transformer is labeled at Transformer 1 and Transformer 2 in the provided diagrams?

Transformer 1 is a step-up transformer; Transformer 2 is a step-down transformer.

What energy conversion takes place in an AC generator?

Mechanical energy is converted to electrical energy.

If the rotation of the armature in a generator is increased, what happens to the induced current?

The induced current INCREASES.

What is an environmental advantage of electricity generation by fossil fuels?

It can provide a stable and continuous power supply.

State one disadvantage of using fossil fuels for electricity generation.

It contributes to greenhouse gas emissions and environmental pollution.

What physical principle is illustrated by moving a bar magnet through a ring to induce current?

Electromagnetic induction.

What is the magnetic flux through a circular coil when it is perpendicular to the magnetic field?

Magnetic flux is calculated using the formula: ext{Flux} = B imes A where B is magnetic field strength and A is area.

What law explains the induced potential difference when the coil rotates in a magnetic field?

Faraday's Law of Electromagnetic Induction.

If a square coil replaces a circular coil while maintaining the same movement, will the induced emf be larger, smaller, or the same?

The induced emf will be SMALLER THAN due to the difference in area calculation.

Suggest two factors that can affect the induced emf in a coil.

Changing the strength of the magnetic field or changing the speed of rotation.

What is a dynamic microphone?

A type of microphone that converts acoustic vibrations into electrical signals.

Describe how a dynamic microphone generates voltage by induction.

It uses a diaphragm connected to a coil that moves within a magnetic field, creating an induced voltage.

Explain the expected time progression of the voltage when the magnet oscillates in a dynamic microphone setup.

The voltage will oscillate according to the frequency of the acoustic vibrations.

What is the maximum induced voltage you can expect in a dynamic microphone?

Depends on the characteristics of the oscillation and the law of induction.