How are the sound of frequency greater than 20 kHz? The human ear cannot sense frequencies above 20000 vibrations per second (20 KHz) in the high-frequency range, and the amplitude of the wave will be dependent on the sound’s loudness. Hence, sound waves having frequency more than 20000Hz are called ultrasonic sound. Can a smartphone produce ultrasonic sound? The phone’s speaker can reproduce a maximum frequency of 18-20 kHz. Ultrasound

What does it mean when you say someone has an old soul? It always seems funny to hear someone say “she has an old soul,” like they can see into their soul. It’s a compliment to be called an old soul. It implies that you are wise beyond your years, with many more ahead of you to make good choices, bring good to the world, and your life. What does

Which method of calculating volume is more accurate? A graduated cylinder should be more accurate than a beaker. Is water displacement more accurate than calculating volume? Since you must measure difference between two measurements, your potential error is doubled. Device to measure volume of water is usually a graduated cylinder, and are accurate to about 0.2\% of the volume you are measuring. What is the most accurate way to measure

How did the Cold War affect American education? The education during the cold war period was geared towards making a giant leap into stabilizing the engineering and scientific fields. The USA government decided to restructure the curriculum to accord students an opportunity of exploring their interest in science and technology. What did the Cold War teach us? The Cold War forced us to think in global terms. In other words,

What are glasses supposed to look like? Your glasses should sit in the middle of your face, no higher than your eyebrows. The total width of your frames should match the width of your face at the temples, leaving enough room on the sides to avoid digging in or leaving marks. Well-fitting glasses will create a sense of visual balance. Is there an app to see what glasses look like

How has Johannesburg changed over time? The area’s identity changed with the discovery of gold in the late 1800s. Since then, Johannesburg has been shaped by mass migration and political developments. With photos from the Getty Images archives, Business Insider South Africa tracked some of the city’s changes since the 1900s. Why the city of Johannesburg grew so fast in 1890? The discovery of coal on the far east Rand

What happened to the other 3 reactors at Chernobyl? Reactor No. 2 was permanently shut down in 1991 after a fire broke out due to a faulty switch in a turbine. Reactors No. 1 and 3 were eventually closed due to an agreement Ukraine made with the EU in 1995. What happened when Reactor 4 exploded? On April 26, 1986, the Number Four RBMK reactor at the nuclear power plant

Which organ is nearest to heart? One important organ in the chest is the thymus, a small butterfly-shaped organ located between the heart and the sternum, or breastbone. What is the 1st organ to receive oxygenated blood? The liver The liver receives a blood supply from two sources. The first is the hepatic artery which delivers oxygenated blood from the general circulation. The second is the hepatic portal vein delivering

How do mangroves create new land? The researchers’ latest work shows that mangroves can facilitate this process, by adding leaf and root structures into the accumulating sediment, which increase the elevation while enhancing the trapping of new sediment arriving from the catchment. How do mangroves build their own environment? Their massive root systems reduce the energy of waves. Mangroves slow the tidal movement of water, allowing sediment to be deposited

What is the meaning of second half of 2021? Second Half-Year Period means the six-month period beginning on July 1st and ending on December 31st of the Plan Year. Sample 1. What does to win 2nd half mean? The term “2nd half betting” applies to football betting (soccer for you North Americans). With “2nd half betting”, you are simply choosing who will score more goals in the second half of