The logarithm from my understanding can never be negative. You can check this on a calculator. You may have a negative if it is shown as -(log x).
Iridium-192 is used in cancer treatment, a small cylindrical piece of 192 Ir, 0.6 mm in diameter (0.3mm radius) and 3.5 mm long, is surgically inserted into the tumor. if the density of iridium is 22.42 g/cm3, how many iridium atoms are present in the sample?
Let us start by computing for the volume of the cylinder. V = π(r^2)*h where r and h are the radius and height of the cylinder, respectively. Let's convert all given dimensions to cm first. Radius = 0.03 cm, height is 0.35cm long.
V = π * (0.03cm)^2 * 0.35 cm = 9.896*10^-4 cm^3
Now we have the volume of 192-Ir, let's use the density provided to get it's mass, and once we have the mass let's use the molar mass to get the amount of moles. After getting the amount of moles, we use Avogadro's number to convert moles into number of atoms. See the calculation below and see if all units "cancel":
9.896*10^-4 cm^3 * (22.42 g/cm3) * (1 mole / 191.963 g) * (6.022x10^23 atoms /mole)
= 6.96 x 10^19 atoms of Ir-122 are present.
I think number one is c not sure or not number 2 is C AND NUMBER 3 IS 1 Go with sliding friction number 2 go with rolling friction number 3 is static friction and 4 is force
I think that answer you are looking for is "The Nucleus" because DNA contains genetic material but the Nucleus directs the cell.
Force: any interaction that, when unopposed, will change the motion of an object.
Mass: the quantity of matter in a body regardless of its volume or of any forces acting on it
Acceleration: rate of change of velocity of an object with respect to time