Category: Physics

How many slaves did Mansa Musa have? 12,000 slaves How rich was Mansa Musa in today’s money? With camel-loads of gold and salt, Mansa Musa’s net worth has been valued by modern-day scholars to be around $400 to $415 billion in modern money. Is King Solomon the richest man ever? Then there’s King Solomon, who […]

Can an elliptical galaxy evolve into a spiral can a spiral turn into an elliptical How? We know this because spiral galaxies rotate quickly (on an astronomical scale), while elliptical galaxies do not. There is no way that an elliptical galaxy could spontaneously begin rotating, so there is no way an elliptical galaxy could turn […]

How do people walk 30 minutes a day? Calories and Fat Burned in 30 Minutes At a brisk walking pace, you would burn 100 to 300 calories in 30 minutes (depending on your weight) or 200 to 600 calories in an hour. By walking for 30 minutes or more at a time, some of those […]

How do you calculate J value? To calculate J for a duplet, simply subtract the lower value from the higher. If the second peak results in a value of 502.68, for example, the value for J would be 2.02 Hz. The peaks within a triplet or quadruplet all have the same spacing, so you’ll only […]

What happens to the molecules of water when it freezes? Point out that when water freezes, the water molecules have slowed down enough that their attractions arrange them into fixed positions. Water molecules freeze in a hexagonal pattern and the molecules are further apart than they were in liquid water. Note: The molecules in ice […]

How does volume affect rms speed? Since the temperature is remaining constant, the average kinetic energy and the rms speed remain the same as well. The volume of the container has decreased, which means that the gas molecules have to move a shorter distance to have a collision. What is the rms speed? The root-mean-square […]

Do longitudinal waves have nodes? Longitudinal wave – a wave that is propagated in the same direction as the displacement of the transmitting medium. Node – A node is a point along a standing wave where the wave has zero amplitude. A wave center is stable at the node of the standing wave. What is […]

What are the causes of shortage of electricity? There are many causes of power failures in an electricity network. Examples of these causes include faults at power stations, damage to electric transmission lines, substations or other parts of the distribution system, a short circuit, cascading failure, fuse or circuit breaker operation. Why electricity is harmful? […]

How does angle affect work? If you apply force at an angle instead of parallel to the direction of motion, you have to supply more force to perform the same amount of work. If you pull at an angle, the component of the force you apply that’s directed along the floor — in the direction […]

How long is a train with 100 cars? 5,200 feet What is the longest freight train in the world? TRANSNET, South Africa, broke its own record for operating the longest freight train, and set a new world record on October 24 when it ran a 375-wagon manganese train on the 861km Sishen – Saldanha heavy-haul […]