Technology Revision Term 3 and 4 Set 3

What is the main function of a Zener diode?

• To amplify current
• To regulate voltage
• To store charge
• To resist current flow

Answer explanation

A Zener diode is primarily used to regulate voltage in a circuit.

Which of the following is NOT a method of food preservation?

• Freezing
• Dehydration
• Fermentation
• Oxidation

Answer explanation

Oxidation is a process that can cause food spoilage, not a method of preservation.

What does PP stand for in plastic recycling?

• Polyethylene Propionate
• Polypropylene
• Plastic Polymer
• Polyvinyl Propylene

Answer explanation

PP stands for Polypropylene in plastic recycling.

Which component in an electronic circuit resists the flow of current?

• Capacitor
• Diode
• Resistor
• Transistor

Answer explanation

A resistor resists the flow of current in an electronic circuit.

What is the main function of an OR gate in digital logic?

• It outputs 1 only if all inputs are 1
• It outputs 1 if any input is 1
• It inverts the input
• It performs multiplication

Answer explanation

An OR gate outputs 1 if any of its inputs are 1.

Which plastic type is commonly used for plastic pipes?

• PET
• HDPE
• PVC
• PS

Answer explanation

PVC (Polyvinyl Chloride) is commonly used for plastic pipes due to its durability and chemical resistance.

What is the main disadvantage of salting as a food preservation method?

• It's expensive
• It destroys nutrients
• It changes the taste of food significantly
• It doesn't work for all types of food

Answer explanation

Salting significantly changes the taste of food, which can be considered a disadvantage.

Which of the following is a characteristic of an NPN transistor?

• Current flows from emitter to collector
• Base must be positive relative to emitter
• It has two P-type semiconductors
• It's only used in analog circuits

Answer explanation

In an NPN transistor, the base must be positive relative to the emitter for current to flow.

What is the main purpose of a grain pit?

• To plant crops
• To process grain
• To store grain
• To transport grain

Answer explanation

A grain pit is a traditional method used to store grain underground.

Which plastic recycling code represents PP?

• 3.0
• 4.0
• 5.0
• 6.0

Answer explanation

PP (Polypropylene) is represented by the recycling code 5.