A solar-powered camping lantern is placed in direct sunlight to charge its battery.
Complete the energy transfer diagram below by identifying the forms of energy at each stage:
Light energy from the Sun⟶[ Energy Form 1 ] energy in the solar panel and cable⟶[ Energy Form 2 ] energy in the battery \text{Light energy from the Sun} \longrightarrow [\ \text{Energy Form 1}\ ] \text{ energy in the solar panel and cable} \longrightarrow [\ \text{Energy Form 2}\ ] \text{ energy in the battery} Light energy from the Sun⟶[ Energy Form 1 ] energy in the solar panel and cable⟶[ Energy Form 2 ] energy in the batteryIt takes 4.5 hours4.5\text{ hours}4.5 hours to fully charge the battery from flat. The average current supplied by the panel is 300 mA.
State the equation linking charge, current, and time.
Calculate the amount of charge needed to fully charge the battery, and state the unit.
If the solar panel is partially shaded by a tree, the output power decreases while the voltage across the solar panel stays constant. Explain how this affects the time needed to fully charge the battery.
25 exam-style questions on Edexcel IGCSE Physics Energy and voltage in circuits. Each one has a worked solution and a mark scheme showing where the marks go.