Description : The half-life of an isotope of an element is 5 days. The mass of a 10 gram sample of this isotope remaining after 20 days is: w) 0.312 grams x) 0.625 grams y) 1.25 grams z) 2.50 grams
Last Answer : ANSWER: X -- 0.625 GRAMS
Description : The time taken for a radioactive element to reduce to 50% of its original weight is __________ years, if its half life period is 12 years. (A) 24 (B) 18 (C) 6 (D) 36
Last Answer : (B) 18
Description : In a spent fuel assembly, the radioactive elements having the longest half-lives are the: w) fission products x) actinides y) activation products z) radioisotopes of lead
Last Answer : ANSWER: X -- ACTINIDES
Description : If the half-life of a radioisotope is 2 days, after how many days is the quantity reduced to 12.5% of its original amount? w) 4 days x) 6 days y) 8 days z) 10 days
Last Answer : ANSWER: X -- 6 DAYS
Description : The density of lead is 12 grams per cm3. A lead brick has a mass of 1.5 kilograms. Its dimensions are 10 cm by 5 cm by 4 cm. Is it: w) More than 75% hollow x) Between 50 and 75% hollow y) Between 25 and 50% hollow z) Between 0 and 25% hollow
Last Answer : ANSWER: Y -- BETWEEN 25 AND 50% HOLLOW
Description : Which of the following is the same for both radioactive iodine and stable iodine? w) number of neutrons x) mass number y) half-life z) chemical properties
Last Answer : ANSWER: Z -- CHEMICAL PROPERTIES
Description : The half life period of a radioactive substance is best determined by counting the number of alpha particles emitted per second in a GeigerMuller counter from its known quantity. If the half life period of a ... in four months (D) 1/8th of it will remain intact at the end of four months
Last Answer : (B) It will completely disintegrate in two months
Description : Radon differs from other naturally radioactive elements in which one of the following ways. Is it because radon w) is extremely radioactive x) decays into the element radium y) is a noble gas z) is as chemically active as fluorine
Last Answer : ANSWER: Y -- IS A NOBLE GAS
Description : The radioactive element most commonly detected in humans is: w) potassium-40 x) cobalt-60 y) iodine-131 z) plutonium-238
Last Answer : ANSWER: W -- POTASSIUM-40
Description : What radioactive element is routinely used in treating hyperthyroidism, and in reducing thyroid activity? w) Iron-59 x) Gold-198 y) Cobalt-60 z) Iodine-131
Last Answer : ANSWER: Z -- IODINE-131
Description : Ten calories of heat are added to 2 grams of water. The temperature of the water rises to a total of how many degrees? Is it: w) 2 degrees Celsius x) 5 degrees Celsius y) 10 degrees Celsius z) 20 degrees Celsius
Last Answer : ANSWER: X -- 5 DEGREES CELSIUS
Description : Two point masses, M1 and M2, are 14 centimeters apart. M1 has a mass of 2 grams. M2 has a mass of 5 grams. Locate the center-of-mass of this system. w) 4 cm from M1 x) 4 cm from M2 y) 5 cm from M2 z) 7 cm from M1
Last Answer : ANSWER: X -- 4 CM FROM M2
Description : In radioactive decay, the emission of an electron is characteristic of: w) Alpha decay x) Beta decay y) Gamma decay z) X-rays
Last Answer : ANSWER: X -- BETA DECAY
Description : The emission of a positron from a radioactive atom is generally accompanied by the emission of one of the following. Is it accompanied by the emission of: w) a meson x) a baryon y) an antineutrino z) a neutrino
Last Answer : ANSWER: Z -- A NEUTRINO
Description : In the sun, helium is produced from hydrogen by: w) radioactive decay x) disintegration y) fission z) fusion
Last Answer : ANSWER: Z -- FUSION
Description : What is the relative humidity when the absolute humidity is 3 grams per cubic meter and the air has a capacity of 12 grams per cubic meter? w) 4% x) 9% y) 25% z) 400%
Last Answer : ANSWER: Y -- 25%
Description : The half life of a radioactive element is 8-days. How long it take to reduce it from 10 mg to 5 mg? A. 4 days B. 12 days C. 16 days D. 8 days (Answer) E. None of these
Last Answer : D. 8 days (Answer)
Description : What is the half-life of a radioactive element ?
Last Answer : Half-life is the amount of time during which half of the nucleus of an element is irradiated.
Description : Francis and George started a business with investments of Rs.7000 and Rs.10000. After x months, Francis left. After two more months David joined the business with an investment of Rs.10000. If the annual profit is shared among David, ... which they stayed that year. a)5:5:12 b)1:1:3 c)1:1:4 d)1:1:2
Last Answer : a)5:5:12
Description : A radioactive element `X`, decays by the sequence and with half-lives, given below, `X underset(30"min")overset(alpha)(rarr) Y underset(2"days")overse
Last Answer : A radioactive element `X`, decays by the sequence and with half-lives, given below, `X underset(30"min" ... D. The mass number of Y is greater than X
Description : X,Y and Z can do a certain job in 72,108 and 144 days respectively. They started the job but X left 16 days before the completion of the job while Y left 24 days before the completion. The number of days for which Z worked is. a) 12 days b) 24 days c) 36 days d) 48 days
Last Answer : D Suppose the work was finished in a' days Then X's (a - 16) day's work + Y's (a - 24) days + Z's a days work = 1 (a-16)/72 + (a-24)/108 + a/144 =1 lcm of 72,108,144 is 432 (6(a-16) + 4( ... = 432 6a - 96 +4a - 96 =3a = 432 13a - 192 = 432 13a = 624 => a =48 Therefore Z worked in 48 days.
Description : For which of the following reasons is plutonium-238 used for generating electricity on spacecraft? w) It is an alpha emitter with long half-life. x) It is a beta emitter with high specific power. y) It occurs abundantly in nature. z) It has low specific power.
Last Answer : ANSWER: W -- IT IS AN ALPHA EMITTER WITH LONG HALF-LIFE.
Description : The half life of tritium is about: w) 3,500 years x) 40 years y) 12.3 years z) 3.7 years
Last Answer : ANSWER: Y -- 12.3 YEARS
Description : A radioactive element `X` has an atomic number of 100. It decays directly into an element `Y` which decays directly into an element `Z`. In both the p
Last Answer : A radioactive element `X` has an atomic number of 100. It decays directly into an element `Y` which decays ... of 100 D. Z has an atomic number of 99
Description : 75% of a radioactive element decays in 6 hours. Its half life period is __________ hours. (A) 3/4 (B) 1/6 (C) 3 (D) 4
Last Answer : (C) 3
Description : The acceleration due to gravity on the moon is 1.6 meters per second squared. If a pendulum is whose length is 6.4 meters is placed on the moon, its period will be: w) 1.57 seconds x) 3.14 seconds y) 12.56 seconds z) 25.12 seconds
Last Answer : not real
Description : A wooden board 2 meters long, 30 centimeters wide and 4 centimeters thick floats in water with 1 centimeter of its thickness above the surface. The mass of the board is: w) 1.8 kilograms x) 18 kilograms y) 24 kilograms z) 176 kilograms
Last Answer : ANSWER: X -- 18 KILOGRAMS
Description : The earth's average density is: w) 2.82 grams per cubic centimeter x) 4.75 grams per cubic centimeter y) 5.52 grams per cubic centimeter z) 10.5 grams per cubic centimeter
Last Answer : ANSWER: Y -- 5.52 GRAMS PER CUBIC CENTIMETER
Description : The oxygen in the earth's atmosphere was probably produced by which of the following? w) volcanos x) photosynthetic organisms y) radioactive minerals z) meteors
Last Answer : ANSWER: X -- PHOTOSYNTHETIC ORGANISMS
Description : Which physical phenomenon or principle is most often applied in the search for petroleum reservoirs? w) magnetic field distortions x) electromagnetic radiation y) natural radioactive decay of minerals z) acoustic wave transmission and reflection
Last Answer : ANSWER: Z -- ACOUSTIC WAVE TRANSMISSION AND REFLECTION
Description : Which physical phenomenon or principle is most often applied in the search for petroleum reservoirs? w) gravitational attraction x) magnetic field distortions y) natural radioactive decay of minerals z) acoustic wave transmission and reflection
Description : Lead-206 is the final product of the radioactive decay series named the: w) thorium series x) actinium series y) uranium series z) neptunium series
Last Answer : ANSWER: Y -- URANIUM SERIES
Description : Radioactive decay is a: w) zero-order process x) temperature-dependent process y) first-order process z) second-order process
Last Answer : ANSWER: Y -- FIRST-ORDER PROCESS
Description : Which of the following scientists was awarded the Nobel Prize in 1911 for the discovery of the radioactive elements, radium and polonium? w) John Dalton x) Dmitri Mendeleev y) Emil Fischer z) Marie Curie
Last Answer : ANSWER: Z -- MARIE CURIE
Description : A copper rod which is 1 centimeter in diameter carries a current of 5 amps. The current is distributed uniformly throughout the rod. The magnetic field half way between the axis of the rod and its ... ) zero. x) pointing radially outward y) pointing radially inward z) circles the axis of the rod
Last Answer : ANSWER: Z -- CIRCLES THE AXIS OF THE ROD
Description : A pendulum which is suspended from the ceiling of a railroad car is observed to hang at an angle of 10 degrees to the left of vertical. Which of the following answers could explain this phenomena? w ... is moving with constant velocity to the right. z) The railroad car is accelerating to the right.
Last Answer : ANSWER: Z -- THE RAILROAD CAR IS ACCELERATING TO THE RIGHT.
Description : A pendulum which is suspended from the ceiling of a railroad car is observed to hang at an angle of 10 degrees to the right of vertical. Which of the following answers could explain this phenomena? ... is moving with constant velocity to the right. z) The railroad car is accelerating to the right.
Last Answer : ANSWER: X -- THE RAILROAD CAR IS ACCELERATING TO THE LEFT.
Description : Initial amount of the radioactive element with half life 10 days is 16 g. What amount in gm of this element will remain after 40 days?
Last Answer : Initial amount of the radioactive element with half life 10 days is 16 g. What amount in gm of this element will remain after 40 days?
Description : The half life period of a radioactive element is 100 days. After 400 days, one gm of the element will be reduced to __________ gm. (A) 1/4 (B) 1/8 (C) 1/2 (D) 1/16
Last Answer : (D) 1/16
Description : How many calories are required to raise the temperature of 20 grams of water from 40 degrees to 60 degrees? w) 40 cal x) 400 cal y) 20 cal z) 200 cal
Last Answer : ANSWER: X -- 400 cal
Description : Which one of the following is largest? w) the number of molecules in 2 grams of hydrogen gas x) the number of molecules in 60 grams of lead sulfate y) the number of molecules in 20 liters of oxygen gas at standard temperature and pressure z) the population of the United States
Last Answer : ANSWER: A - THE NUMBER OF MOLECULES IN 2 GRAMS OF HYDROGEN GAS
Description : How many moles of carbon are in 48 grams of carbon w) 4 x) 3 y) 2 z) 1
Last Answer : ANSWER: W -- 4
Description : Normality is defined as the number of: w) moles of solute per 1000 grams of solvent x) equivalent weights of solute per liter of solution y) kilograms of solute per liter of solution z) moles of solute per 1000 grams of solution
Last Answer : ANSWER: X -- EQUIVALENT WEIGHTS OF SOLUTE PER LITER OF SOLUTION
Description : If you started with 100 grams of each of the materials below and they all vaporized inside of an inflatable balloon, which of them would produce the largest volume balloon, assuming they were all at the same temperature? w) water x) gasoline y) ethanol z) butane
Last Answer : ANSWER: W -- WATER
Description : Of the following, which non-fissioning element is used in the cooling water of nuclear power plants to help control the rate of the fission reaction by absorbing neutrons: w) zirconium x) boron y) krypton z) cesium
Last Answer : ANSWER: X -- BORON
Description : An element has the following numbers of electrons in its shells: 2-8-8-2. Which of the following is true? The element: w) is a nonmetal x) forms an ion with a charge of +2 y) can accept two electrons z) forms a negative ion
Last Answer : ANSWER: X -- FORMS AN ION WITH A CHARGE OF +2
Description : Isotopes of an element have different numbers of: w) electrons x) protons y) neutrons z) leptons
Last Answer : ANSWER: Y -- NEUTRONS
Description : What is the only non-metal element that is a liquid at room temperature and one atmosphere? w) bromine x) argon y) silicon z) selenium
Last Answer : ANSWER: W -- BROMINE
Description : What happens to the period of a pendulum if the mass of the bob is quadrupled? w) it is cut in half x) it stays the same y) it is doubled z) it is quadrupled
Last Answer : ANSWER: X -- IT STAYS THE SAME
Description : If the distance between the centers of mass of two bodies is doubled, the gravitational force between the bodies will become what portion of the original force: w) double x) one half y) remain the same z) one quarter
Last Answer : ANSWER: Z -- ONE QUARTER