Energy

Figure 4 shows a person sliding down a zip wire. Describe how the vertical height of the tower could be measured accurately.

When using the zip wire, the person moved through a vertical height of 2.0 m. The person has a mass of 45 kg. gravitational field strength = 9.8 N/kg. Calculate the change in gravitational potential energy of the person. Use the equation: gravitational potential energy = mass × gravitational field strength × height

Give three factors that affected the kinetic energy of the person as she reached the bottom of the zip wire.

Figure 6 shows how different energy resources were used in the United Kingdom (UK) to generate electricity on one day in June 2018. The UK government plans to stop using coal-fired power stations by 2025. Explain one environmental problem caused when electricity is generated by burning coal.

Give two renewable energy resources that could make up the ‘Other’ energy resources in Figure 6.

Determine the percentage of electricity generated in nuclear power stations that day. Use data from Figure 6.

Figure 7 shows how the demand for electricity varied with the time of day. What was the difference between the maximum demand and minimum demand for electricity during this day?

Figure 7 shows that the demand for electricity increased between 06:00 and 09:00. Solar power could have met the demand if there were enough solar panels installed in the UK. Explain why.

An electric car has a motor that is powered by a battery. A diesel car has an engine that is powered by diesel fuel. Table 2 compares an electric car and a diesel car. Give two advantages of the diesel car compared with the electric car in Table 2.

The mass of the battery in the electric car is 420 kg. The total mass of the electric car is 1610 kg. Calculate the mass of the battery as a percentage of the total mass of the electric car.

Designers of electric car batteries want to increase the amount of energy that can be stored in a battery. Suggest two reasons why.

Write down the equation which links energy transferred, power and time.

The charger has a power output of 7000 W. Calculate the time taken to transfer 420 000 J of energy to the car battery.

A student carried out an experiment to determine the specific heat capacity of water. Figure 12 shows the equipment the student used to heat the water. Why did the student insulate the beaker of water?

One hazard in this experiment is the hot water. Give one risk to the student caused by this hazard.

Wind turbines may generate electricity when the electricity is not needed. Two methods that can be used to store the energy from the turbine are: Method A: Heating water to a high temperature. Method B: Pumping water uphill into a reservoir. Which energy store increases when water is heated?

Which energy store increases when water is pumped uphill into a reservoir?

The table shows information about the two methods of storing energy. <br/><br/> <table border="1" cellpadding="12" cellspacing="0" style="border-collapse: collapse; font-family: Arial, sans-serif; font-size: 14px; border: 2px solid black;"> <tr> <th style="border: 1px solid black; padding: 12px; font-weight: bold;">Method</th> <th style="border: 1px solid black; padding: 12px; text-align: center; font-weight: bold;">Energy stored<br/>per 100 kg of<br/>water in kJ</th> <th style="border: 1px solid black; padding: 12px; text-align: center; font-weight: bold;">Percentage of<br/>stored energy<br/>wasted</th> <th style="border: 1px solid black; padding: 12px; text-align: center; font-weight: bold;">Installation</th> </tr> <tr> <td style="border: 1px solid black; padding: 12px;"><b>A:</b> Increasing water<br/>temperature by 80 °C</td> <td style="border: 1px solid black; padding: 12px; text-align: center;">33 600</td> <td style="border: 1px solid black; padding: 12px; text-align: center;">40%</td> <td style="border: 1px solid black; padding: 12px; text-align: center;">Anywhere</td> </tr> <tr> <td style="border: 1px solid black; padding: 12px;"><b>B:</b> Pumping water uphill to<br/>a height of 500 m</td> <td style="border: 1px solid black; padding: 12px; text-align: center;">490</td> <td style="border: 1px solid black; padding: 12px; text-align: center;">25%</td> <td style="border: 1px solid black; padding: 12px; text-align: center;">High<br/>mountains</td> </tr> </table> <br/><br/> Compare the advantages and disadvantages of the two methods of storing energy. Include calculations in your answer.

Decreasing the amount of carbon dioxide released by different activities will help slow down climate change. Transport and generating electricity are the two activities that released the largest amounts of carbon dioxide in the UK in 2018. Explain **one** change that would reduce the amount of carbon dioxide released by **each** activity. Transport: Generating electricity:

Use the Physics Equations Sheet to answer questions 02.2 and 02.3. Write down the equation which links energy (E), power (P) and time (t).

A nuclear power station has a power output of 500 MW. Calculate the energy output in 3600 s. Give your answer in J.

Nuclear power stations do not generate electricity every day of the year. One nuclear power station generated electricity for 92% of a year. one year = 365 days Calculate the number of days during the year that the nuclear power station generated electricity.