Question 1: Define static electricity and explain how it differs from current electricity.

Answer: Static electricity is the build-up of electric charge on the surface of objects, which remains stationary. Unlike current electricity, which involves the flow of electrons through a conductor, static electricity involves charge accumulation without continuous flow.

Question 2: Describe a common way static electricity can be generated in a car during driving.

Answer: Static electricity can be generated when the tires rub against the road surface, causing friction that transfers electrons between the tires and the road, leading to charge build-up on the vehicle.

Question 1: A car's body accumulates a static charge of 1.2 microcoulombs due to friction with the road. How much electric charge (in coulombs) is accumulated?

Answer: 1.2 × 10^-6 C

Question 2: If a static discharge occurs when the accumulated charge on a vehicle drops from 1.2 microcoulombs to zero over 0.5 seconds, what is the average current during the discharge?

Answer: 2.4 microamperes

Question 1: Outline the safety precautions that should be taken when working with static electricity in automotive repair shops.

Answer: Precautions include wearing grounding straps to prevent charge buildup, avoiding contact with conductive parts during static discharge, ensuring proper grounding of equipment, and working in dry environments to reduce static risk.

Question 2: Describe a simple experiment to demonstrate static charge transfer between a car tire and a metal object.

Answer: Rub a rubber balloon or plastic rod against wool to generate static charge, then bring it close to the metal object attached to the car tire. Observe the attraction or repulsion, indicating charge transfer.

Question 1: A vehicle with a static charge of 0.8 microcoulombs experiences a discharge, reducing its charge to zero in 0.4 seconds. What is the average charge transfer per second?

Answer: 2 microcoulombs per second

Question 2: In an automotive assembly plant, static charges build up on car bodies during painting. Why is it important to control static electricity in this process?

Answer: Controlling static electricity prevents sparks that could ignite flammable paint fumes, ensures proper paint adhesion, and avoids damage to electronic components.

Question 1: Explain the process by which static electricity can cause a car to spark when opening the door after driving on a dry day. Include in your answer how this is related to charge flow and safety precautions that can be taken.

Answer: When a car is driven on a dry day, friction between the tires and the road causes electrons to transfer, building a static charge on the vehicle's body. Upon opening the door, the charge may discharge suddenly through a spark, especially if a conductive part or metal handle is touched, potentially causing a small electric shock or igniting flammable fumes. To prevent this, grounding straps can be used to equalize charge, or the vehicle can be touched to a grounded metal part before opening the door. This process illustrates charge flow from the vehicle to the ground, reducing the risk of static shocks.