Question 1: An electric field is a region around a charged object where other charged objects experience a force. The strength of this field depends on the amount of charge and the distance from the charge.

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

Question 1: Define electric field strength and write its SI unit.

Answer: Electric field strength is the force experienced per unit positive charge at a point in the field; SI unit is newtons per coulomb (N/C).

Question 2: Explain why the electric field around a positively charged sphere points outward.

Answer: Because the positive charges repel other positive charges and attract negative charges, so the field lines radiate outward from the positive charge.

Question 1: Calculate the electric field strength at a distance of 0.5 meters from a point charge of 2.0 μC. Use the formula E = kQ/r², where k = 9.0 x 10⁹ N·m²/C².

Answer: E = 72,000 N/C

Question 2: A small charged sphere has a charge of 5 μC and experiences an electric field of 1.0 x 10⁴ N/C. What is the magnitude of the force acting on a 2 μC test charge placed in this field? (Use F = qE).

Answer: F = 20 N

Question 1: Describe a simple experiment to demonstrate the presence of an electric field around a charged object. Include the variables you would control and safety precautions.

Answer: One possible experiment involves using small pith balls suspended by non-conductive threads near a charged rod. Variables to control include the charge on the rod and the distance of the pith balls. Safety precautions include grounding the charged object to prevent accidental discharge and avoiding contact with high-voltage sources.

Question 1: A point charge of 3 μC creates an electric field of 1.2 x 10⁴ N/C at a distance of 0.3 meters. Explain how the electric field strength would change if the distance from the charge is doubled.

Answer: The electric field strength would decrease to a quarter of its original value, so E = 3 x 10³ N/C, because electric field strength is inversely proportional to the square of the distance.

Question 1: Explain how electric fields are utilised in photocopiers or laser printers.

Answer: Electric fields are used to manipulate toner particles, attracting them to specific areas on the paper to form images, by controlling charged toner particles with electric fields.

Question 2: Identify one safety precaution that must be taken when working with high-voltage electric fields in industrial settings.

Answer: Ensure proper grounding of equipment and wear insulating gloves to prevent electric shocks.