A school is setting up a new science laboratory. The electrician has to select suitable materials for different electrical connections. Four materials—aluminium, iron, sulfur, and coal—are tested to determine whether they allow electricity to pass through them.
During the testing, the electrician observes that aluminium and iron allow electricity to pass easily, whereas sulfur and coal do not allow electricity to pass through them effectively. Based on these observations, the conducting materials are selected for electrical wiring in the laboratory.
Go through the case carefully and answer the following questions.
1. Which materials were selected for electrical wiring? -
2. If sulfur were used instead of aluminium for wiring the laboratory, what would most likely happen? -
3. Which conclusion can be drawn from the investigation? -
4. A student says, "Coal should also be used for electrical wiring because it is available in large quantities." Which statement best evaluates this idea? -