The table gives data for four different electrical devices.
| Device | Voltage | Current |
|---|---|---|
| USB charger | 5.0 V | 2.0 A |
| LED street light | 240 V | 0.15 A |
| High-voltage insulator leakage | 150 kV150\text{ kV}150 kV | 0.05 mA |
| Laptop adapter | 19 V | 3.2 A |
Which device develops the least power?
USB charger
LED street light
High-voltage insulator leakage
Laptop adapter
452 exam-style questions on CIE IGCSE Physics 4.2 Electrical quantities, covering 4.2.1a Positive and negative charge, 4.2.1b Charging by friction and detecting charge, 4.2.1c Electrical conductors and insulators, 4.2.1d Electric fields and electric field patterns, 4.2.2a Electric current, charge and measuring current, 4.2.2b Conduction in metals and the direction of current, 4.2.2c Direct current and alternating current, 4.2.3a Electromotive force, 4.2.3b Potential difference and voltmeters, 4.2.4a Resistance, 4.2.4b Resistance of a metallic wire, 4.2.4c Current–voltage graphs, and 4.2.5 Electrical energy and electrical power. Each one has a worked solution and a mark scheme showing where the marks go.