Using a calorimeter.

 I find that many students have not used a colorimeter or even what one looks like. Their idea of an entropy experiment is to heat a beaker of water, not considering heat loss. Comparing two experiments, we had a difference of hundreds of Joules.

Circle to a sine wave

 Using a Lego model to convert a circular motion into a sine wave to demonstrate the relationship between the trig functions and the circle.

Bartons Pendulums

 Setting up Barton's Pendulums to demonstrate resonance on a string is a breeze with this kit from @lascells. It's fascinating to see how the driving frequency of one ball influences the others. The ball of the same length starts to swing, absorbs the energy, and causes the first to stop—then the cycle repeats!

Understanding Resonance Through Barton's Pendulum

Resonance is a powerful and captivating phenomenon in physics that explains how oscillating systems can transfer energy between each other. It occurs when a system is driven at its natural frequency, leading to a dramatic amplification of the oscillations. One of the most striking demonstrations of resonance is the Barton's Pendulum. This simple yet effective setup offers a hands-on way to visualize the concept of resonance in motion.

What is Resonance?

Before diving into Barton's Pendulum, let's first understand resonance. Every object or system has a natural frequency at which it tends to vibrate. When an external force or energy is applied at this natural frequency, the object begins to oscillate with increasing amplitude, resulting in resonance.

This is like pushing a swing at just the right moment. If you push at the swing's natural frequency (the timing when it moves the most), you can make it swing higher and higher. The energy from your pushes accumulates in the system, amplifying the motion.

Resonance can be found in many physical systems, from musical instruments like guitars and violins to the human body and even in buildings during earthquakes. It plays a key role in both engineering and natural phenomena, both helping and hindering the design of structures and devices.

What is Barton's Pendulum?

Barton's Pendulum is a classic physics demonstration that vividly shows how resonance works in a mechanical system. It consists of a string with a series of pendulums (small swinging balls) attached to it, with one pendulum being used as the driving force and the others as passive receivers.

In this setup, one ball is set into motion with a push, and its oscillations start to drive the motion of other balls that are attached to the same string. The key point here is that the balls on the string have different lengths (and hence, different natural frequencies). When the driving ball oscillates at a frequency that matches the natural frequency of one of the other balls, it transfers energy to that ball. This ball begins to swing in sync with the driving ball, causing the first ball to stop. The energy transfer continues as the pendulums oscillate back and forth in a repeating cycle.

How Does Barton's Pendulum Demonstrate Resonance?

The beauty of Barton's Pendulum lies in its ability to visually show the transfer of energy between oscillating bodies. Here's how it works step-by-step:

1. The Driving Ball: One ball (often the first one) is given an initial push to start it oscillating.

2. Energy Transfer: As this ball swings back and forth, it imparts energy to the other balls. The key is that this energy transfer only occurs effectively when the driving ball matches the natural frequency of another ball.

3. Synchronization: When the balls on the string are of the same length (or close to it), they share the same natural frequency. When the driving ball hits the right frequency, it will begin to synchronize with another ball, causing that ball to swing and absorb energy from the first one.

4. Oscillation Cycle: The cycle repeats. As one ball receives energy, the other stops moving and the process begins again. This continuous transfer of energy is a direct demonstration of the resonance phenomenon.

Why Does This Happen?

This energy transfer occurs because of the natural frequency of each pendulum. When a ball is driven at its resonant frequency, the amplitude of its oscillation increases. Since the pendulums are connected by the string, they share this energy, and it causes the other pendulums to swing in response.

The exact mechanics of the transfer are dictated by the physics of waveforms and resonance. When the frequency of the driving ball matches the natural frequency of a passive pendulum, energy flows efficiently between them, amplifying the oscillations.

Why Is Barton's Pendulum Important?

The Barton's Pendulum is an excellent teaching tool for understanding the principle of resonance. It offers a clear and visually engaging way to explain an often abstract concept. Additionally, it highlights the importance of resonant frequencies in mechanical systems, which has real-world applications in fields such as engineering, architecture, and even medicine.

Applications of Resonance

Understanding resonance and its applications is crucial for engineers and designers. In construction, for example, resonance is taken into account when designing buildings, bridges, and other structures to ensure they can withstand vibrations caused by factors like wind, traffic, or even earthquakes.

In technology, resonance is used in musical instruments, electrical circuits, and tuning systems to enhance performance and efficiency. It also plays a vital role in medical devices, such as MRI machines, where specific resonant frequencies are used to produce clear images of the body.

Conclusion

Barton's Pendulum is an intriguing demonstration that brings the abstract concept of resonance to life. By showing how energy is transferred between oscillating bodies, it makes it easy to visualize how resonance can amplify motion. From its fundamental principles to its real-world applications, resonance is a fascinating phenomenon that continues to influence many fields, from engineering to medicine. Whether you're a student or a science enthusiast, the Barton's Pendulum setup is a perfect tool to explore the power of resonance in action.

Hornwort

 Trying to find a good aquatic plant for photosynthesis experiments in the laboratory. Hornwort (Ceratophyllum dermersum) does about the best. Being a native species, it grows well in my pond all year round, so it also has good availability.

Evidence for brain damage

​Should schoolchildren head the ball? In our ​ A Level Psychology class we dug into whether lighter balls are truly safer and if heading could lead to brain damage. Research reveals some surprising insights!

Benzene

 Looking at a structural model of the benzene bonds to see if we can understand why it reacts the way it does and how we arrived through history to this model.

Momentum

 Investigating Momentum with elastic and inelastic collisions using the @pascoscientific smartcarts. Using either the velcro or the magnets, simple collisions can be measured, and using multiple stacked carts, we can simulate changing the mass visually.

Two Protractors

 Two protractors, the one on the left makes it easy for the students to do bearings, and the one on the right is the one that students have in their pencil case, which makes doing bearings much more difficult.

Total Internal reflection

 Seeing what we can do with total internal reflection - communicating down fibres, lighting Christmas trees and using endoscopes.

Knitted Gut

 c

Poverty is complex

A-level Sociology Poverty is complex—no single measure tells the full story. Stats are just snapshots in time. The amount of income is only a vague yardstick. By using different measures & perspectives, we get a clearer picture. #Sociology

Model 100

 Taking my 1980’s Tandy Trs-80 out for a spin. The students wondered what I could do with a computer with no internet. We looked at the text editor and the spreadsheet and watched the daisy wheel printer work.

I Love Science

 I Love Science

Physics in Action

 One of my students filmed their high-board dive, and we processed the footage using @pascoscientific Capstone to analyze the motion in detail—calculating speed, acceleration, and more! #PhysicsInAction #MotionAnalysis

Visualising Physics in Mechanics

 Creating an Atwood machine to simulate a lift to help non-physicists visualise and then solve Mechanics problems.

Showing refraction in water

 A quick demo for the students on the refraction of a laser when the beam hits the water's surface. The dye shows up the path of the laser, so it is very easy to see what happens.

Circulation

Connecting a model heart with tubes simulating the parts of the body the tubes go to and return from and then making the heart beat to observe how the blood flows. Using lots of air in the system helps see the blood flow more easily.
 

Win for Team GB in Australia

 A great weekend of watching the SailGP in Australia and a great win for Team GB

Inventory Metrics

 Learning all about inventory turnover metrics: turnover, carriage costs, order fill rate, average days to sell an inventory, the item fill rate, the cycle time and the return on the investment. And someone said this was trivial!

Preparing the computers

 ​Prep work: Loading the Raspberry Pi's with a new copy of Linux, Apache, PHP, MariaDB, docker, and Phpmyadmin so we are ready to create websites and do all things server.

Bond Angles

 ​I just taught an online lesson on bond angles across a period.  We explored how molecular shapes maximize distances between groups, why some molecules are bent instead of linear, and how trigonal bipyramidal structures have different bond angles. Fascinating stuff! #Chemistry

Electrical experiments

 Just 10 minutes to recap the three electrical components ( resistor, bulb and diode) used to make the voltage vs. current graphs. Just as quick as drawing them using the @pascoscientific voltage current sensor and Capstone and three circuits made and experiments done in 10 minutes.

A bit Dicey

 

Probability took a turn for the worse when the students had to work out the probability of throwing a number on different dice. They discovered that investigation was needed rather than making assumptions.

Ball Bearings in freefall

Creating a strobe image of two ball bearings falling. One falls vertically and the other is propelled sideways. The camera used a flash on a strobe setting capturing an image every 1/15 of a second.

 

All in a Heartbeat

 Taking an ECG on a student in A-Level Biology using the @pascocienctific ECG sensor. Using a digital stethoscope, the students could record and play back their heartbeat and tie this in with the ECG that they recorded.

Oxytocin in Psychology

 A-Level Psychology: Oxytocin, the "bonding hormone," is naturally released during sex, childbirth, and breastfeeding. As a synthesized drug, it's been explored as a potential treatment for various psychiatric disorders. #Psychology #Oxytocin

DBMS and GIS

 A-level Computing DBMS and GIS. Another real-world use for relational databases? Integrating them with GIS to pinpoint houses near a river, optimize delivery routes, or count homes in a school zone.