15 22
Related questions
Question
100%
I need help with number 7
Transcribed Image Text:6:45 9
Untitled document (75).pdf
Honors Physics: Test 2, March15,22
Directions: Show your work by including tables, mathematical formulas, and necessary units.
1. If the "N" number of atoms of a radioactive substance had decayed to 25 atoms in five
half-lives, what was the original number of atoms in the substance?
2. If a sample known to be about 17190 years old has 400 carbon-14 atoms, how many
atoms were in the sample when the organism died? Half-life of C-14 is 5730 years.
3. If we start with 64 grams of a radioactive substance, what percent will remain after four
half-lives?
4. How old is a bone if it presently contains 0.125 gm of C-14, but it was estimated to have
originally contained 160 gm of C-14.? The half-life of C-14 is 5730 years.
5. What is the half-life of a radioactive isotope if a 600 gm sample decays to 48 grams in 27
hours?
6. The formula of converting temperature from Celsius to Fahrenheit is:
" = 1.8x c° + 32. and the formula for converting Celsius to Kelvin scale is:
K=+ 273.
(a) Convert these Fahrenheit scales to Celsius scales: 70"F, 180°F, and 18°F
(b) Convert these Celsius scales to Kelvin scales: 20°C; 100°C; 160°c
(c) Convert this Fahrenheit scale to Kelvin scale: 140"F.
7. The temperature of a substance changes from 300°F to 400°F. What is the equivalent
change in Kelvin scale?
8. A student measures the mass of a 12 cm - block of brown sugar is 15 gm
What is the density of the brown sugar?
9. A machine shop worker records the mass of an aluminum cube as 170 gm. If one side of
the cube measures 6 cm, what is the density of the aluminum?
10. A substance has a volume of1 cubic meter and density of 3kg/m'. What would be its
mass in grams. (Hint convert kg to gram and meter to centimeter and then use the
density formula, which is: Density= Mass/Volume
(1m =100 cm;
1 kg -1000 gm)
11. The dimensions of a block are 12cm, 6cm, and "X" cm. Assuming the block has a mass
of 12 kg and its density is 4 kg/m'. What is the value of "X" in meters? (Hint: Change
centimeters to meters and then use the density formula, which is: Density-Mass/Volume
12. An oscillator makes four vibrations in one second, what is its frequency and period?
Expert Solution
This question has been solved!
Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.
Step by step
Solved in 2 steps with 2 images
