Question 1: Define electromagnetic induction and explain how it is utilised in nanotechnology devices.

Answer: Electromagnetic induction is the process of generating an electric current in a conductor by changing the magnetic field around it. In nanotechnology, it is used to create nanoscale sensors and energy harvesters by inducing currents through magnetic flux changes.

Question 2: Describe the mechanism by which a changing magnetic field induces a current in a nanoscale wire.

Answer: A changing magnetic field alters the magnetic flux through the nanoscale wire, inducing an electromotive force (emf) that causes electrons to move, thus generating a current.

Question 3: What is magnetic flux, and how does its change relate to the induction of current?

Answer: Magnetic flux is the measure of the magnetic field passing through a given area. A change in magnetic flux induces an emf, leading to current in the conductor.

Question 1: A nanoscale coil with an area of 2 x 10^-12 m^2 experiences a change in magnetic flux from 4 x 10^-8 Wb to zero over 0.01 seconds. Calculate the average induced emf using Faraday's Law.

Answer: EMF = ΔFlux / ΔTime = (4 x 10^-8 Wb - 0) / 0.01 s = 4 x 10^-6 V

Question 2: If a nanoscale magnetic sensor has a coil with 500 turns and experiences an emf of 2 x 10^-6 V during a flux change, what is the change in magnetic flux if the flux change occurs over 0.005 seconds?

Answer: ΔFlux = EMF x ΔTime / Number of turns = (2 x 10^-6 V) x 0.005 s / 500 = 2 x 10^-11 Wb

Question 1: Design a basic experiment using a nanoscale wire or coil to demonstrate electromagnetic induction. List the variables you would control and the safety precautions necessary.

Answer: To demonstrate induction, set up a nanoscale coil connected to a sensitive voltmeter. Variable control includes the rate of change of magnetic flux (by moving a magnet or changing magnetic field strength), coil orientation, and magnetic field strength. Safety precautions involve handling strong magnets carefully to avoid pinching or injury and ensuring the nanoscale components are handled with appropriate tools to prevent damage or contamination.

Question 1: A nanotechnology company develops a magnetic energy harvester that operates by changing magnetic flux at a rate of 1 x 10^-4 Wb per second through a nanoscale coil with 1000 turns. What is the induced emf? Explain its significance for energy harvesting.

Answer: Using Faraday's Law: EMF = N x ΔFlux / ΔTime = 1000 x 1 x 10^-4 Wb / 1 s = 0.1 V. This induced emf can generate usable electrical energy at the nanoscale, enabling efficient energy harvesting in tiny devices.

Question 1: Explain how electromagnetic induction is used in nanoscale sensors within medical nanorobots. (6 marks)

Answer: In medical nanorobots, electromagnetic induction is used to detect changes in magnetic fields caused by biological signals. Nanoscale coils or sensors detect these changes by inducing currents when magnetic flux varies, enabling precise, wireless communication and real-time monitoring of physiological conditions.