Answer:
option (c) is correct
Explanation:
Half life of a substance is the time in which the element becomes half of is initial value.
half life, T = 8 days
Amount remaining, N = 10 % of original value
Let the original value is No.
N = 10% of No
N = 0.1 No
Let the time taken is t and the decay constant is λ.
The relation between the decay constant and the half life is given by
Us the equation of radioactivity
Taking natural log on both the sides, we get
0.08664 t = 2.303
t = 26.6 days
Answer:
The pieces will attract one another
Explanation:
From the law of conservation of energy, we know that energy can neither be created nor destroyed, but transformed. If one piece of the toy that was neutral ends up having an electric charge (positive or negative), from the conservation of energy, the other piece must have a charge opposite to that on the other charged piece but equal in magnitude. These two pieces which are oppositely charged attracts each other, this shows that electric charge is conserved.
This is the answer to what a hypothesis may also be called
Answer:
D. 803 lbs
Explanation:
In order to find the compressive stress on all three blocks we first need to find the normal surface area of each:
Surface Area of 1 Block = 3.5 x 3.5
Surface Area of 1 Block = 12.25
Surface Area of all 3 Blocks = A = 3 x 12.25
Area = 36.75
Now, the stress is given by the following formula:
Stress = Force/Area
Stress = 29500 lbs/36.75
Stress = 802.72 lbs
Hence, the correct option will be:
<u>D. 803 lbs</u>
Answer:
.864 M
Explanation:
For first order decomposition,
rate constant k = 1/t x ln a / (a - x )
given , a = 1.33 M , t = 644 s , k = 6.7 x 10⁻⁴ , a - x = ? = b( let )
6.7 x 10 ⁻⁴ = 1/644 x ln 1.33/b
ln 1.33/b = 6.7 x 10⁻⁴ x 644 = .4315
1.33 / b = e⁰ ⁴³¹⁵ = 1.5395
b = 1.33 / 1.5395 = .864 M.
