Answer: 0.333 h
Explanation:
This problem can be solved using the <u>Radioactive Half Life Formula</u>:
(1)
Where:
is the final amount of the material
is the initial amount of the material
is the time elapsed
is the half life of the material (the quantity we are asked to find)
Knowing this, let's substitute the values and find
from (1):
(2)
(3)
Applying natural logarithm in both sides:
(4)
(5)
Clearing
:
(6)
Finally:
This is the half-life of the Bismuth-218 isotope
Answer:
m≈501.57 g
Explanation:
The density formula is:
d=m/v
Let’s rearrange the formula for m. m is being divided by v. The inverse of division is multiplication, so multiply both aides by v.
d*v= m/v*v
d*v=m
The mass can be found by multiply the density and the volume.
m=d*v
The density is 1.06 grams per milliliter and the volume is 473.176 milliliters.
d= 1.06 g/mL
v= 473.176 mL
Substitute the values into the formula.
m= 1.06 g/mL * 473.176 mL
Multiply. When multiplying, the mL will cancel out.
m= 501.56656 g
Let’s round to the nearest hundredth. The 6 in the thousandth place tells us to round the 6 to a 7 in the hundredth place.
m ≈501.57 g
The mass is about 501.57 grams.
the answer is (a) molecules
Answer:
The distance by the ball clear the crossbar is 1.15 m
Explanation:
Given that,
Distance = 44 m
Speed = 24 m/s
Angle = 31°
Height = 3.05 m
We need to calculate the horizontal velocity
Using formula of horizontal velocity

Put the value into the formula


We need to calculate the vertical velocity
Using formula of vertical velocity

Put the value into the formula


We need to calculate the time
Using formula of time

Put the value into the formula


We need to calculate the vertical height
Using equation of motion

Put the value into the formula


We need to calculate the distance by the ball clear the crossbar
Using formula for vertical distance

Put the value of h


Hence, The distance by the ball clear the crossbar is 1.15 m