Why are stealth bombers invisible? They are not completely invisible, but they are able to reduce the reflection of radar, infrared, visible light, and radio waves. The first stealth plane was the Lockheed F-117 Nighthawk built in 1981. It was an attack aircraft, not a bomber, but it was the first plane to make use […]
#428 Why are stealth bombers invisible? Read More »
How far will the Voyager probes go? As far as they can get before they are eroded to nothing by space dust. Voyager 1 and 2 were both launched in 1977. As of today, December 4th 2022, Voyager 1 is about 23.7 billion kilometers from the sun and Voyager 2 is about 19.8 billion kilometers
#427 How far will the Voyager probes go? Read More »
What is the difference between snowflakes and hail? Snowflakes are made up of ice crystals and hail is a frozen raindrop. Hail are frozen raindrops. They are generally between 5 mm and 15 cm in diameter. Hail is not as common as snow and can only form in a thunderstorm. For hail to form there
#426 What is the difference between snowflakes and hail? Read More »
How does an air fryer work? A fan circulates hot air at high speed which cooks the food. Firstly, let’s look at how food cooks when it is fried. With deep-frying, food is submerged in oil that is heated to between 177 and 191˚C. That seems pretty hot, but it is far below the boiling
#425 How does an air fryer work? Read More »
How do mammals keep warm in the winter? They have several different methods. Here are some of them. Many mammals stay warm by putting on more fat. Sea mammals have to cope with very cold ocean water and it is harder to stay warm in water than it is on land. If you are naked
#424 How do mammals keep warm in the winter? Read More »
Why are there twelve months in a year? Because it is the closest match to the number of times the moon orbits the Earth in a year. Before there were names for the months, people lived by a lunar calendar. There was no need to know what month it was or what day it was.
#423 Why are there twelve months in a year? Read More »
What causes quicksand? It forms in saturated loose sand when the sand is suddenly agitated. Quicksand is an example of a non-Newtonian fluid. That means it is a liquid, but has the properties of a solid when the pressure applied to it changes. A Newtonian fluid is a liquid such as water that flows exactly
#422 What causes quicksand? Read More »
How many revolutions has France had? France has had three revolutions and they are currently on their fifth republic. The first revolution was the big one. The one we learn about in school as “The French Revolution”. It started in 1789 and it ushered in the first republic. It began because of rising inequality in
#421 How many revolutions has France had? Read More »
What is in toothpaste? It usually has fluoride, abrasives, flavors, humectants, and detergents. So, what do all of these things do? Fluoride is a naturally occurring mineral. It can be found in most places on Earth, and it is also present in our bodies. Our bodies use it to strengthen our bones and teeth. Fluoride
#420 What is in toothpaste? Read More »
What are the four laws of thermodynamics? I didn’t know there were four laws until researching this. Thermodynamics is the study of the relationship between heat, temperature, and energy. The 0th law of thermodynamics states that if two systems are in thermodynamic equilibrium with a third system, the first two systems are in equilibrium with
#419 What are the four laws of thermodynamics? Read More »
