Question 1: Define an electric field in your own words.

Answer: An electric field is the region around a charged object where other charged objects experience an electric force.

Question 2: Explain the mechanism by which a charged object creates an electric field.

Answer: A charged object creates an electric field due to the presence of electric charge, which exerts a force on other charges within the surrounding space, extending outward in all directions.

Question 1: Calculate the electric field strength at a point 0.5 meters away from a charge of 2 microcoulombs. Use the formula E = k * |Q| / r^2, where k = 9 x 10^9 N·m²/C².

Answer: E = 9 x 10^9 * 2 x 10^-6 / (0.5)^2 = 72 N/C

Question 2: A charge of 5 microcoulombs is placed at a point. If the electric field strength at a certain point is 180 N/C, what is the distance from the charge to that point? Rearrange the formula to find r: r = sqrt(k * |Q| / E).

Answer: r = sqrt(9 x 10^9 * 5 x 10^-6 / 180) ≈ 0.498 meters

Question 1: Describe the safety precautions that should be taken when working with high-voltage electric charges in a laboratory setting.

Answer: Ensure equipment is properly insulated, keep a safe distance from high-voltage sources, wear insulating gloves, and follow proper grounding procedures.

Question 2: Identify the variables that would affect the strength of an electric field in an experimental setup.

Answer: The magnitude of the charge, the distance from the charge, and the environment's dielectric properties.

Question 1: A spherical charge of 3 microcoulombs produces an electric field of 36 N/C at a distance of 1 meter. Based on this data, determine if the electric field strength follows the inverse square law. Provide a brief explanation.

Answer: Since the electric field strength is proportional to 1 / r^2, doubling the distance should reduce the field by a factor of four. Comparing data at different distances confirms this relationship, indicating the electric field follows the inverse square law.

Question 1: Explain how electric fields are used in the technology of photomultiplier tubes. (6 marks)

Answer: Electric fields in photomultiplier tubes are used to accelerate electrons emitted from a photosensitive surface. These electrons are then multiplied through a series of dynodes by controlled electric fields, producing a measurable current proportional to the incident light intensity, enabling sensitive light detection.

Question 1: Describe how electric fields are utilized in the design of electrostatic precipitators used in pollution control.

Answer: Electric fields are used to charge particles in the flue gases, causing them to be attracted to and collected on oppositely charged plates, thereby removing pollutants from emissions.

Question 2: Explain the role of electric fields in the operation of inkjet printers.

Answer: Electric fields are used to direct and control tiny ink droplets, precisely positioning them onto paper to form images or text.