<h3>
Answer:</h3>
15.29 minutes
<h3>
Explanation:</h3>
<u>We are given;</u>
- Original number of counts = 1668 counts
- New number of counts = 1330 counts
- Time is 5 minutes
We are required to determine the half life of the sample;
- We know that half life is the time it takes for a radioactive sample to decay by a half of the original amount.
- To calculate the remaining mass after decay we use the formula;
- N = N₀ × 0.5^n , where N is the remaining amount, N₀ is the original amount and n is the number of half lives.
- Using the formula we can calculate the value of n;
1330 counts = 1668 counts × 0.5^n
Thus,
0.5^n = 0.79736
Introducing logarithm;
n log 0.5 = log 0.79736
Thus,
n = 0.327
But, n = time ÷ half life
Thus,
Half life = time ÷ n
= 5 minutes ÷ 0.327
= 15.29 minutes
Thus, the half life of the unknown sample is <u>15.29 minutes</u>
Grav Force = GMm/r squared. M is earth's mass. m is the probe. r is distance to centre of earth.Given that 600 = GMm/(10,000^2).GMm = 600x(10,000^2) for 10, 000 milesGMm = ? x (20,000^2) for 20, 000 milestherefore600x(10,000^2)=? x (20,000^2)therefore [600x(10,000^2)]/(20,000^2)=? [600x(1x1)]/(2x2)=? [600/4]=? ?=150lb.Same procedure for b and c.Please ask if you want further help.
C. <span>skin color
</span>Which example best describes an inherited trait that can be determined by looking at a individual? skin color
<span>NOT:
</span>a.
good memory
b.
diet that affects feather color
d.
<span>accent while speaking
</span>
Answer:
e. is definitely zero
Explanation:
Given that
At initial condition the speed of the pop cans is zero.
We know that linear momentum
P = Mass x velocity
P = m v
At initial condition v = 0
P= 0
If there is no any external force then the linear momentum of the system will be conserve.And given that ,consider the system isolated.
Therefore the answer is e.
Answer:
Q1: (a)
so
Q2:
this is the radius in meter
diameter = 2r
in this i don't know which choice is the right answer
Q3:
so
again there is no correct answer