create a video to explain and solve the practical questions---UNIVERSITY OF LAGOS DEPARTMENT OF PHYSICS B.SC DEGREE (HONS) EXAMINATION 1ST SEMESTER 2023/2024 ACADEMIC SESSION PHS 218: PRACTICAL PHYSICS TIME ALLOWED: 2¼ HOURS COURSE UNIT: 1 UNIT INSTRUCTIONS: ANSWER ALL QUESTIONS. DO NOT WRITE ANYTHING ON THIS QUESTION PAPER DURING THE EXAM. ALL WRITINGS SHOULD BE DONE IN YOUR ANSWER BOOKLET. 1. Clamp one end of the meter rule at 5cm mark on the desk and suspend or attach a mass of 50grams at the other end. Set the mass into oscillation and record the time for 10 oscillations. Repeat the oscillation twice for a total of three readings. Repeat the experiment by clamping the meter rule at the following marks; 15cm, 25cm, 35cm and 45cm. Measure the time for 10 oscillations three times for each mark. Tabulate your readings. Given the period of oscillation as follows: T = 2π√(ML³/3EI) T² = 4π²ML³/3EI T² * 3EI = 4π²ML³ E = (4π²M / 3I) * (L³ / T²) where E is the Young's Modulus of the beam, M is the suspended or attached mass, L is length of the meter rule that oscillates and I is moment of inertia expressed as: I = wd³/12 (2) where w and d are the breadth and thickness of the meter rule respectively. Plot a suitable graph based on the variable quantities measured in equation(1). Determine Young's Modulus from your graph. (15 marks) (a) Define Young's Modulus. (1 marks) (b) What is the consequence if the meter rule used in this experiment is perfectly rigid?(3 marks) (c) State one precaution for this experiment. (1 marks) 2. You are provided with dry cells E, key K, potentiometer AB with jockey J, resistance box RB, resistances R1 and R2, galvanometer G and connecting wires: connect the circuit shown below.

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Welcome to the Young's Modulus experiment. In this practical physics lab, we will determine the Young's Modulus of a meter rule using the oscillation method. We clamp one end of the meter rule at different positions and attach a fifty gram mass at the free end. By measuring the oscillation periods at various clamping positions, we can calculate the Young's Modulus using the given formula. Welcome to the Young's Modulus experiment from the University of Lagos Physics Department. In this practical examination, we will analyze an oscillating meter rule to determine the Young's Modulus of the material. This experiment demonstrates how mechanical oscillations can reveal important material properties. Now let's examine the experimental procedure step by step. First, we clamp the meter rule at the five centimeter mark and attach the fifty gram mass at the free end. We set the mass into small vertical oscillations and time ten complete oscillations using a stopwatch. This measurement is repeated three times for accuracy. We then repeat the entire process by clamping the rule at fifteen, twenty five, thirty five, and forty five centimeter marks. Notice how the oscillating length L changes with each clamping position. The theoretical foundation of this experiment is based on the oscillation of a cantilever beam. When a mass is attached to the free end of a clamped meter rule, it oscillates with a period given by the formula T equals two pi times the square root of M L cubed divided by three E I. Here, M is the mass, L is the oscillating length, E is Young's Modulus, and I is the moment of inertia. By rearranging this equation, we can solve for Young's Modulus in terms of the measured quantities. For data analysis, we plot T squared versus L cubed. This should give us a straight line passing through the origin, since the relationship is linear. The slope of this line equals four pi squared M divided by three E I. From the slope, we can calculate Young's Modulus using the formula E equals four pi squared M divided by three I times the slope. The moment of inertia I is calculated from the dimensions of the meter rule. Let's review the key concepts. Young's Modulus is defined as the measure of a material's resistance to elastic deformation, expressed as the ratio of stress to strain. If the meter rule were perfectly rigid, no bending would occur and there would be no oscillation, making the period infinite. Important precautions include ensuring small oscillation amplitudes, avoiding air currents during timing, taking multiple readings for accuracy, and measuring all dimensions carefully. This experiment demonstrates how mechanical properties can be determined through oscillation analysis. The theoretical foundation of this experiment is based on the oscillation of a cantilever beam. When a mass is attached to the free end of a clamped meter rule, it oscillates with a period given by the formula T equals two pi times the square root of M L cubed divided by three E I. Here, M is the mass, L is the oscillating length, E is Young's Modulus, and I is the moment of inertia. By rearranging this equation, we can solve for Young's Modulus in terms of the measured quantities. For data analysis, we plot T squared versus L cubed. This should give us a straight line passing through the origin, since the relationship is linear. The slope of this line equals four pi squared M divided by three E I. From the slope, we can calculate Young's Modulus using the formula E equals four pi squared M divided by three I times the slope. The moment of inertia I is calculated from the dimensions of the meter rule. To summarize what we have learned: Young's Modulus is a fundamental material property that measures stiffness and resistance to elastic deformation. The oscillation method provides an accurate experimental technique for determining this important constant. The linear relationship between T squared and L cubed validates our theoretical understanding of cantilever beam mechanics. Proper experimental procedures ensure reliable and reproducible results that are essential for engineering applications.