| How is accuracy ensured when determining the resistance for each length l? | The experiment is repeated twice more, and the mean resistance R is recorded for each length. |
| A 1m long constantan wire used to investigate electrical properties. | Constantan Wire |
| An instrument used to measure the potential difference across the wire. | Voltmeter |
| A device used to measure the current flowing through the circuit. | Ammeter |
| A power source that provides a safe and adjustable voltage for the experiment. | Low Voltage Power Supply |
| A tool used to measure the diameter of the wire with high precision. | Micrometer |
| A ruler used to measure the length of the wire accurately. | Metre Ruler |
| What is the first step in setting up the stationary waves on a string experiment? | Set up the apparatus as shown in the diagram |
| How is the diameter of the constantan wire measured? | Using a micrometer to measure the diameter at various points along the wire, then calculating the mean diameter. |
| How is the length l of the wire adjusted during the experiment? | The length l is adjusted to 0.100m using crocodile clips, measured with a metre ruler. |
| How are the current I and voltage V recorded during the experiment? | The current I is read on the ammeter, and the voltage V is read on the voltmeter. |
| What formula is used to calculate the resistance R of the wire? | The formula R = V / I is used to calculate the resistance. |
| How is the resistance R measured for different lengths of the wire? | The resistance R is calculated for increasing lengths l, starting from 0.100m and increasing by 0.100m each time up to 0.800m. |
| How is accuracy ensured when determining the resistance for each length l? | The experiment is repeated twice more, and the mean resistance R is recorded for each length. |
| The cross-sectional area A of the wire can be calculated using the formula A = πd²/4, where d is the diameter of the wire. | Cross-sectional Area of the Wire |
| How do you calculate the cross-sectional area A of the wire? | The cross-sectional area A can be calculated using the formula A = πd²/4, where d is the diameter of the wire. |
| A graph of the mean value of resistance (R) against the length l should be plotted, with a line of best fit. | Graph of Resistance vs Length |
| What should be plotted to analyze the resistivity of the wire? | Plot a graph of the mean value of resistance (R) against the length l and draw a line of best fit. |
| The resistivity ρ of the material can be found by multiplying the gradient G of the graph by the cross-sectional area A of the wire: ρ = GA. | Resistivity Formula |
| How is the resistivity ρ of the wire calculated? | The resistivity ρ of the material can be found by multiplying the gradient G of the graph by the cross-sectional area A of the wire: ρ = GA. |
| The resistivity of the material is proportional to the gradient of the graph, multiplied by the cross-sectional area of the wire: ρ = GA. | Resistivity and Gradient |
| What does the gradient G of the graph represent in terms of resistivity? | The gradient G of the graph represents the relationship used to calculate resistivity, as ρ = GA. |
| Disconnect the crocodile clips between measurements to prevent the wire from heating up, which could cause burns if touched. | Disconnecting Crocodile Clips |
| Why should the crocodile clips be disconnected between measurements? | The crocodile clips should be disconnected to prevent the wire from heating up, which could cause burns if touched. |
| If the current rises too high, the voltage should be reduced using the variable power supply. | Reducing Voltage |
| What should be done if the current rises too high during the experiment? | The voltage should be reduced using the variable power supply. |
| Safety goggles should be worn if the wire is tight to protect the eyes in case it snaps and causes injury. | Safety Goggles |
| When should safety goggles be worn during the experiment? | Safety goggles should be worn if the wire is tight to protect the eyes in case it snaps and causes injury. |
| Wire heating can cause the resistance of the wire to change, affecting measurements. To reduce this, disconnect the wire between measurements or reduce the voltage to lower the current. | Wire Heating and Resistance |
| How can wire heating affect the measurements, and how can it be minimized? | Wire heating can change the resistance, affecting measurements. It can be minimized by disconnecting the wire between measurements or reducing the voltage to lower the current. |
| The wire should be free from kinks and held straight to ensure the length measurement is as accurate as possible. | Straightening the Wire |
| Why should the wire be free from kinks and held straight during the experiment? | The wire should be straight to ensure the length measurement is as accurate as possible. |
