Физика, 10-й класс, Лабораторная работа «Изучение равномерного прямолинейного движения»

Summary

The video lesson focuses on studying uniform linear motion through a laboratory experiment. The aim is to examine the motion of an air bubble in a sealed glass tube by measuring the time it takes to travel set distances. The experiment involves dividing the distance into smaller segments to calculate average speeds and identify uniform motion. The lesson also explores how varying the tube's angle and using different liquids, such as water and oil, affect the bubble's speed. Key findings highlight the relationship between speed, inclination, and liquid viscosity, concluding with an analysis of experimental errors.

Takeaways

• 🔬 The lesson focuses on studying uniform rectilinear motion through experimental methods.
• 🧪 The main experiment involves using a sealed glass tube, a millimeter ruler, a block to adjust the tube's angle, and a stopwatch.
• 🫧 The objective is to demonstrate that an air bubble moves uniformly in a straight line within the tube.
• 📏 The distance between the start and finish lines in the experiment is 40 centimeters, and the time is measured for multiple trials to ensure accuracy.
• ⏳ The tube's distance is divided into halves and quarters to further measure the time taken for the bubble to move over smaller segments.
• 📊 A graph is plotted based on the data collected, showing a linear relationship between displacement and time, confirming uniform motion.
• 🚀 The average speed of the air bubble is calculated as 0.0318 meters per second, with a relative error of 0.5%.
• 🔧 The experiment is repeated with varying tube inclinations, demonstrating that increasing the angle increases the bubble's speed.
• 🌡️ Another part of the experiment compares the bubble's speed in water and oil, showing that the bubble moves slower in oil due to higher viscosity.
• 📈 Final conclusions affirm that the motion of the air bubble is uniform and linear, with speed depending on both the tube's angle and the liquid's viscosity.

Q & A

What is the main objective of the lab experiment described in the lesson?

The main objective is to study uniform rectilinear motion using experimental methods, specifically by observing the movement of an air bubble in a glass tube.

What equipment is required for this lab experiment?

The required equipment includes a glass tube sealed at both ends (about 50 cm long), a millimeter ruler or measuring tape, a block to adjust the tube’s incline, and a stopwatch.

How is the uniformity of the air bubble's motion verified?

The uniformity is verified by measuring the time it takes for the air bubble to travel between a start and finish line multiple times, then dividing the distance in half and quarters to measure time in smaller segments.

Why are multiple measurements taken during the experiment?

Multiple measurements are taken to increase the accuracy of the results by averaging the times, reducing random errors, and improving the reliability of the data.

What is the purpose of dividing the distance into halves and quarters?

Dividing the distance into halves and quarters helps to check whether the air bubble maintains a constant speed over smaller segments, reinforcing the uniformity of the motion.

How is the graph of the bubble's motion used in the experiment?

The graph plots the bubble’s displacement over time, and the linearity of this graph confirms that the motion is uniform. The slope of the graph corresponds to the bubble’s speed.

What is the average speed of the air bubble, and how is it calculated?

The average speed of the air bubble is calculated to be 0.0318 m/s. It is determined by selecting any point on the graph, calculating its coordinates, and using the slope of the line (displacement over time).

How is experimental error accounted for in the experiment?

Experimental error is accounted for by calculating the relative error, which involves the precision of the measuring tools (ruler and stopwatch) and the deviation of measurements. The error in speed is found to be 0.0002 m/s.

What effect does increasing the inclination of the tube have on the bubble’s speed?

Increasing the inclination of the tube causes the average speed of the air bubble to increase, as shown by repeating the experiment with higher tube inclines and observing faster times.

What difference in bubble speed is observed when using different liquids in the tube?

The experiment shows that the air bubble moves slower in oil than in water. This is because the viscosity of the liquid affects the speed, with more viscous liquids like oil reducing the bubble’s speed.