Understanding Current and Voltage Basics

Front

Electric current and its unit

Back

The flow of electric charge; measured in amperes

Answer explanation

Electric current is defined as the flow of electric charge, typically carried by electrons. It is measured in amperes (A), making the second answer choice correct.

Front

Voltage

Back

The potential difference between two points; measured in volts

Answer explanation

Voltage is defined as the potential difference between two points in an electric field, which drives the flow of electric charge. It is measured in volts, making the second answer choice the correct one.

Front

Pro of using electric vehicles?

Back

They produce zero emissions

Answer explanation

The correct choice is 'They produce zero emissions' because electric vehicles are environmentally friendly, contributing to reduced air pollution, unlike traditional petrol cars that emit harmful gases.

Front

Which of the following is a con of using electric vehicles?

• They produce zero emissions
• They have a limited range
• They are cheaper to maintain
• They are quieter than petrol cars

Back

They have a limited range

Answer explanation

A con of using electric vehicles is that they have a limited range compared to petrol cars, which can restrict long-distance travel without frequent recharging.

Front

What is the relationship between current, voltage, and resistance in a circuit?

Back

Answer explanation

The correct relationship is given by Ohm's Law, which states that voltage (V) equals current (I) multiplied by resistance (R), expressed as V = I × R. This fundamental principle governs how electrical circuits operate.

Front

What voltage is typically required for household appliances in Great Britain?

Back

230V

Answer explanation

In Great Britain, the standard voltage for household appliances is 230V. This is the voltage supplied by the electrical grid, making it the correct choice among the options provided.

Front

Why are some car manufacturers moving to 800V systems?

Back

To reduce charging time

Answer explanation

Car manufacturers are moving to 800V systems primarily to reduce charging time. Higher voltage allows for faster charging rates, making electric vehicles more convenient and efficient for users.

Front

What is the rule for current in a series circuit?

Back

Current is the same through all components

Answer explanation

In a series circuit, the same current flows through all components. This means that the current is not divided or altered; it remains constant throughout the circuit.

Front

What is the rule for voltage in a parallel circuit?

Back

Voltage is the same across all branches

Answer explanation

In a parallel circuit, the voltage across each branch is the same. This means that all components connected in parallel experience the same voltage, making the correct choice "Voltage is the same across all branches."

Front

How should an ammeter be connected in a circuit?

Back

In series with the component

Answer explanation

An ammeter measures current and must be connected in series with the component to ensure all the current flows through it. Connecting it in parallel would bypass the ammeter, leading to inaccurate readings.