Explanation

• Iron is a ferromagnetic material, which means it is strongly attracted to magnets.
• Therefore, an iron kettle will be attracted to a magnet.

Explanation

• Wood is an insulator and cannot conduct electricity.
• So it cannot be used to complete a circuit.

Explanation

• An open circuit provides an incomplete path for the current to flow through.
• As the circuit is broken or disconnected, preventing electricity from flowing.

Explanation

• A closed circuit provides a complete path for the current to flow through.
• It allowing electricity to flow from the power source, through the wire, and back to the power source.

Explanation

• An open circuit is an electrical circuit that is broken or disconnected, and electricity cannot flow.
• When the wire is disconnected, the circuit is open, and the bulb is off.

Explanation

• A close circuit, also known as a closed circuit.
• It is an electrical circuit that is complete and allows electricity to flow from the power source, through the wire, and to the bulb, causing it to light up.

Explanation

• Insulators are materials that resist the flow of electricity, such as rubber, glass, wood, and plastic.
• They have a high resistance to electric current and are used to prevent the flow of electricity.

Explanation

• Sounds travel faster through solids than through both gases and liquids.
• Solids have a more rigid structure, allowing sound waves to propagate more efficiently and at a faster speed.

Here's a comparison of sound speeds in different materials:

• Solids (e.g., steel): up to 5,960 m/s (13,140 ft/s)
• Liquids (e.g., water): up to 1,482 m/s (4,862 ft/s)
• Gases (e.g., air): approximately 343 m/s (1,125 ft/s)

Explanation

• Sound travels through a physical medium, such as air, water, or solid objects.
• It is transmitted through the vibration of particles in the medium.

Explanation

A compound machine is a machine that is made up of two or more simple machines.

A bicycle, a crane, wheel borrow and scissors are examples of compound machines because they are made up of multiple simple machines, such as:

• Wheels and axles (simple machine: wheel)
• Pedals and levers (simple machine: lever)
• Gears and pulleys (simple machine: pulley)
• Inclined planes (simple machine: inclined plane)