10 most difficult physics riddles A list of ten (out of 80) physics related questions that are the most often answered incorrectly Physics quiz The speed to let the rocket enter the orbit is ...VI = 7,91 km/s. And cosmic velocity - also referred to as the circular velocity, it is the speed that should be given to the body to enter into orbit around Earth.very hard 15% vI = 7,91 km/svI = 7,91 km/s15%vII = 11,19 km/svII = 11,19 km/s35%vIII = 16,7 km/svIII = 16,7 km/s15%Depends on the weight of the rocketDepends on the weight of the rocket34%Created by: Tschuka. Statistics based on 4165 answers in 2 languages »weapons riddles » In which layer of the atmosphere the aurora is created?In the Thermosphere. Auroras are produced when the magnetosphere is sufficiently disturbed by the solar wind that the trajectories of charged particles in both solar wind and magnetospheric plasma, mainly in the form of electrons and protons, precipitate them into the upper atmosphere (thermosphere/exosphere) due to Earth's magnetic field, where their energy is lost. very hard 18% In the TroposphereIn the Troposphere21%In the StratosphereIn the Stratosphere38%In the mesosphereIn the mesosphere20%In the ThermosphereIn the Thermosphere18%Created by: Tschuka. Statistics based on 766 answers in 2 languages »atmosphere riddles » What is the name of the most radioactive isotope on the planet?Polonium 210. 210Po is extremely toxic, with one microgram being enough to kill the average adult (250,000 times more toxic than hydrogen cyanide by weight).210Po was used to kill Russian dissident and ex-FSB officer Alexander V. Litvinenko in 2006,very hard 19% Rad 226Rad 22615%Uranus 235Uranus 23542%Polonium 210Polonium 21019%plutonium 244plutonium 24422%Created by: Tschuka. Statistics based on 464 answers in 2 languages »chemical elements riddles » Saffir-Simpson scale is used to measure ...Hurricane force. Officially, the Saffir–Simpson hurricane wind scale is used only to describe hurricanes forming in the Atlantic Ocean and northern Pacific Ocean east of the International Date Line. Other areas use different scales to label these storms, which are called "cyclones" or "typhoons", depending on the area.very hard 20% Speed supersonic jetsSpeed supersonic jets8%Shock wave at nuclear explosionShock wave at nuclear explosion49%Hurricane forceHurricane force20%Thunderbolt forceThunderbolt force21%Created by: Tschuka. Statistics based on 211 answers in 3 languages »weather riddles » What does synthesis gas (water gas) consist of?Carbon monoxide (CO) and hydrogen (H2). Water gas is a mixture of carbon monoxide and hydrogen produced from synthesis gas. Synthesis gas is a useful product, but requires careful handling due to its flammability and the risk of carbon monoxide poisoning. The water-gas shift reaction can be used to reduce the carbon monoxide while producing additional hydrogen, resulting in water gas. very hard 21% oxygen (O2) and hydrogen (H2)oxygen (O2) and hydrogen (H2)21%methane (CH4) and water (H2O)methane (CH4) and water (H2O)32%carbon dioxide (CO2) and hydrogen (H2)carbon dioxide (CO2) and hydrogen (H2)24%carbon monoxide (CO) and hydrogen (H2)carbon monoxide (CO) and hydrogen (H2)21%Created by: Tschuka. Statistics based on 3081 answers in 3 languages »water riddles » What is the name of the wind measuring device?Anemometer. An anemometer is a device used for measuring the speed of wind, and is also a common weather station instrument. The term is derived from the Greek word anemos, which means wind, and is used to describe any wind speed measurement instrument used in meteorology. very hard 22% DynamometerDynamometer18%PedometerPedometer9%HydrometerHydrometer49%AnemometerAnemometer22%Created by: Tschuka. Statistics based on 1510 answers in 2 languages »measures riddles » Which type of transmission uses the shortest waves?Satellite TV. The Ku band is the portion of the electromagnetic spectrum in the microwave range of frequencies from 12 to 18 gigahertz (GHz). Ku band is primarily used for satellite communications, most notably for fixed and broadcast services, and for specific applications such as NASA's Tracking Data Relay Satellite used for both space shuttle and International Space Station very hard 23% GSM telephonyGSM telephony15%CB radioCB radio34%VHF radioVHF radio25%satellite TVsatellite TV23%Created by: Tschuka. Statistics based on 4200 answers in 3 languages »TV riddles » What disease does stephen hawking have?Lou Gehrig's disease ALS. Hawking has a rare early-onset, slow-progressing form of amyotrophic lateral sclerosis (ALS) that has gradually paralysed him over the decades. He now communicates using a single cheek muscle attached to a speech-generating device.very hard 25% Balo concentric sclerosisBalo concentric sclerosis11%Multiple Sclerosis MSMultiple Sclerosis MS42%Creutzfeldt-Jakob disease CJDCreutzfeldt-Jakob disease CJD20%Lou Gehrig's disease ALSLou Gehrig's disease ALS25%Created by: Tschuka. Statistics based on 327 answers in 3 languages »medicine riddles » Who discovered radioactivity?Henri Becquerel. Antoine Henri Becquerel (15 December 1852 – 25 August 1908) was a French physicist, Nobel laureate, and the first person to discover evidence of radioactivity. For work in this field he, along with Marie Skłodowska-Curie and Pierre Curie, received the 1903 Nobel Prize in Physics. The SI unit for radioactivity, the becquerel (Bq), is named after him.very hard 26% Henri BecquerelHenri Becquerel26%Max PlanckMax Planck9%Ernest RutherfordErnest Rutherford26%Maria Skłodowska-CurieMaria Skłodowska-Curie38%Created by: Tschuka. Statistics based on 446 answers in 3 languages »discoverers riddles » The idea that the nascent universe passes through the phase of exponential expansion, which was driven by the positive density of vacuum energy, is called;Cosmic inflation. Alan Guth formally proposed the idea of cosmic inflation in 1981, the idea that the nascent universe passed through a phase of exponential expansion that was driven by a positive vacuum energy density (negative vacuum pressure).very hard 27% Cosmic inflationCosmic inflation27%Grand unification theoryGrand unification theory25%Theory of SupersymmetryTheory of Supersymmetry15%All answers are correct.All answers are correct.31%Created by: Tschuka. Statistics based on 4798 answers in 2 languages »universe riddles » Play physics quiz and see all the questions.