Today, we're tackling a common and curious observation: Why do the leaves of tea collect in the center of a cup after stirring? Have you ever stirred your tea or coffee and noticed how the loose tea leaves seem to gather right in the middle, seemingly defying expectations? It feels counterintuitive when you'd expect them to be pushed outwards, doesn't it? Let's dive into the science behind this baffling effect!

100 Everyday Science Questions Answered

Why does a bicycle stay upright when it's moving, despite being unstable when still?It's a mix of the bicycle's steering geometry (caster effect) and the rider's crucial active balance adjustments.This combination helps the front wheel steer into leans, providing passive and active stabilization to keep the bike upright.

⁠100 Everyday Science Questions Answered⁠

Ever notice how spilled coffee often leaves a ring as it dries, rather than an even stain? It's caused by evaporation and capillary flow drawing dissolved particles towards the edge of the liquid drop. This concentrates the solids at the periphery, resulting in that characteristic ring shape.

⁠100 Everyday Science Questions Answered⁠

Have you ever noticed how wet things always look darker than when they are dry? It's a common observation, but why does it happen?

In this episode, we're exploring the underlying physics of how light interacts with materials to explain this phenomenon. When a material gets wet, water fills the spaces within it. Because water has a higher index of refraction than air, less light is reflected away from the surface, and more light is able to enter the material. This light then travels deeper and is absorbed more by both the material and the water.

Have you ever pondered the seemingly contradictory nature of space? It's a vacuum, devoid of air, yet it isn't perpetually freezing cold. This podcast episode dives into the intriguing physics behind this phenomenon. We'll unravel the difference between temperature, a measure of particle motion, and heat, which is energy transfer. Discover why the vacuum of space drastically limits heat transfer through conduction and convection, the two mechanisms we're most familiar with on Earth. Instead, we'll explore the crucial role of radiation, primarily from the Sun, as the dominant way objects in space gain or lose energy. Learn how the Sun's immense energy can cause objects in direct sunlight to become incredibly hot, even hotter than a summer day on Earth, while those in shadow can become extremely cold due to the lack of other heat transfer mechanisms. Join us to understand why space itself doesn't have a temperature in the way we understand it on Earth, and why the temperature of objects in space is all about the balance of radiation.

The Book

Have you ever wondered where the rubber from your worn-out car tires goes? This podcast episode delves into the fascinating, and perhaps surprising, journey of those vanishing treads. We explore the underlying physics of tire wear, revealing that the rubber doesn't simply disappear but is transformed into microscopic particles due to friction and abrasion with the road surface. These tiny particles, measured in micrometers, become airborne and dispersed into the environment. While a single tire might lose only about 0.3 kg of rubber over its life, we uncover how this seemingly small amount accumulates to millions of tons of rubber polluting our air and waterways globally each year. Join us to learn more about this hidden environmental impact of our everyday journeys.

The book

Is it possible to drown in 100% humidity? Join us as we delve into the science behind those hot, sticky days when the air feels thick with moisture. We'll explore what 100% relative humidity truly signifies, revealing that it indicates the air is saturated with water vapour at a given temperature, not that the air is full of liquid water. Understand the crucial difference between water vapour, a gas, and liquid water. Tune in to bust the myth and gain a clear understanding of what really happens when the humidity hits 100%.

The book

This episode delves into the perplexing phenomenon of why mirrors appear to swap our left and right sides but not our top and bottom. Have you ever noticed that when you raise your right hand, your reflection seems to raise its left ? Yet, when you nod, your reflection also nods in the same direction? We'll unpack the underlying physics that governs how mirrors work to reveal the fascinating truth behind this everyday illusion

This episode explains the common phenomenon of a shower curtain moving inwards during a shower. It identifies the cause as a difference in air pressure created by the moving water and entrained air. This movement of water generates a low-pressure zone inside the shower stall, while the air pressure outside remains higher. Consequently, the higher external pressure pushes the lightweight curtain towards the area of lower pressure, a principle related to fluid dynamics and Bernoulli's principle.