Y10 Waves Starter II

A major problem of renewable energies like Solar and Wind is that they cannot store their energy for future use, meaning any excess energy that is not used by consumers at the time is wasted.

This is done by having any excess energy spin a large, high-friction turbine.

What TWO energy stores does the excess energy transfer to?

• Kinetic

• Thermal

• Chemical

• Gravitational

Hydroelectric Power Plants can be combined with Solar and Wind to combat this lack of storage.

When water flows from the reservoir to the river, the ​ (a)   store of the water decreases via a ​ (b)   pathway.

This increases the ​ (c)   store of the turbine as the water flows through.

The generator then transfers energy via the ​ (d)   pathway to the homes and industries in the area.

• gravitational
• mechanical
• kinetic
• electrical
• thermal
• chemical
• heating
• radiation

Wind turbines can be hooked up to a pump that pumps water from the river back up to the reservoir to be used in the hydroelectric station.

This means that ​ (a)   energy produced by the wind turbine will not be ​ (b)   , when demand for energy is low.

The reservoir acts as a ​ (c)   for the energy produced by the wind turbine.

This means the hydroelectric power station can keep producing energy even when ​ (d)   is high, along with the wind turbine.

• excess
• wasted
• battery
• demand
• all of
• high
• generator

What are the differences between BOILING and EVAPORATION?

Groups:

(a) Boiling

,

(b) Evaporation

• Can happen at any temperature (when the substance is a liquid)

• Happens throughout the entire liquid

• Temperature of the liquid remains the same

• Only happens at the surface of the liquid

• Temperature of the liquid decreases

• Only happens at a specific temperature

Which of these best define the term refraction?

• When a wave changes direction due to a change in speed when entering a different medium.

• When a wave changes direction due to slowing down when entering a material that is more dense.

• When light changes speed, causing it to change direction.

An oscilloscope is a device that displays waves on a screen, known as a trace.

On the trace shown, the x-axis represents 10 ms per division on the square grid.

The y-axis represents 5V per division on the square grid.

Which of these is an appropriate estimate of the amplitude of this wave?

• 11V

• 22V

• 20ms

• 40ms

An oscilloscope is a device that displays waves on a screen, known as a trace.

On the trace shown, the x-axis represents 10 ms per division on the square grid.

The y-axis represents 5V per division on the square grid.

What is the FREQUENCY of this wave?

(Frequency = 1 / Time Period)

• 25 Hz

• 50 Hz

• 0.025 Hz

• 0.050 Hz

When a wave enters a material with a higher refractive index (denser material), it will...

• Slow down and bend towards the normal

• Speed up and bend away from the normal

• Slow down and bend away from the normal

• Speed up and bend towards the normal

When a wave enters a material with a lower refractive index (less dense material), it will...

• Slow down and bend towards the normal

• Speed up and bend away from the normal

• Slow down and bend away from the normal

• Speed up and bend towards the normal

When a nebula collapses under its own weight, which energy store increases, beginning from before it begins collapsing to just before it begins to fuse hydrogen and form a star?

• Gravitational

• Thermal

• Nuclear

• Chemical