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

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
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ANSWER: X -- 0.625 GRAMS
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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

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

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If you start with 24 grams of a radioactive element with a half-life of one month, how many grams of the radioactive element will be left after 2 months? w) 1.5 grams x) 3 grams y) 6 grams z) 12 grams

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The half life of radioactive isotope is 3 hour. If the initial mass of isotope were 256 g, the mass of it remaining undecayed after 18 hr is a)12 g b)

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If a sled has a constant acceleration of 2 meters per second squared and starts from rest, the distance in meters that it will have covered after 5 seconds is: w) 10 meters x) 20 meters y) 25 meters z) 50 meters

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A 10 kilogram mass rests on a horizontal frictionless surface. A horizontal force of 5 Newtons is applied to the mass. After the force has been applied for 1 second, the velocity of the mass is: w) 0 meters per second x) 0.5 meters per second y) 5 meters per second z) 50 meters per second

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The amount of a radioisotope remaining undecayed after a time equal to four times its half life, will be __________ percent. (A) 3.125 (B) 6.25 (C) 12.50 (D) 25

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Last Answer : ANSWER: Z -- 100

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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

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The mass, in kilograms, of an object whose weight on earth at sea level is 490 newtons is: w) 50 kilograms x) 100 kilograms y) 225 kilograms z) 1,100 kilograms

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A train locomotive whose mass is 1 x 106 kilograms is traveling EAST at a speed of 100 kilometers per hour. A NORTHERLY wind is applying a force of 100 Newtons on the locomotive. How much work is the wind doing on the locomotive for each 10 meters it travels? w) 0 joules x) 1,000 joules y) 10,000 joules z) 100,000 joules

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