Answer:
(a) 
(b) 15 hours
Explanation:
half life, T = 12 hours
No = 19 g
(a) Let N be the amount remaining after time t.
Let λ be the decay constant.
The equation of radioactivity used here is given by
(b) N = 8 gram
Substitute the values in above equation
λ = 0.0577 per hour
So, 
Take natural log on both the sides
- 0.0577 t = - 0.865
t = 15 hours
1.) 7, humans have the same amount of neck bones. Think of it that way
2.) It has a pattern diamond like or web like.
3.) Indian wild dog
Answer:
a) dB / dA = 2
,
b) Network B Network A
2 1
4 2
6 3
Explanation:
a) The expression for grating diffraction is
d sin θ = m λ
where d the distance between two slits, λ the wavelength and m an integer that represents the diffraction range
In this exercise we are told that the two spectra are in the same position, let's write the expression for each network
Network A
m = 1
sin θ = 1 λ / dA
Network B
m = 2
sin θ = 2 λ / dB
they ask us for the relationship between the distances, we match the equations
λ / dA) = 2 λ / dB
dB / dA = 2
b) let's write the equation of the networks
sin θ = m_A λ / dA
sin θ = m_B λ / dB
we equalize
m_A λ/ dA = m_B λ / dB
we use that
dB / dA = 2
m_A 2 = m_B
therefore the overlapping orders are
Network B Network A
2 1
4 2
6 3
<h2>Answer: Francium
</h2>
Let's start by explaining that electronegativity is a term coined by Linus Pauling and is determined by the <em>ability of an atom of a certain element to attract electrons when chemically combined with another atom.
</em>
So, the more electronegative an element is, the more electrons it will attract.
It should be noted that this value can not be measured directly by experiments, but it can be determined indirectly by means of calculations from other atomic or molecular properties of the element. That is why the scale created by Pauling is an arbitrary scale, where the maximum value of electronegativity is 4, assigned to Fluorine (F) and the <u>lowest is 0.7, assigned to Francium (Fr).</u>
Answer:
40 m/s.
Explanation:
From the question given above, the following data were obtained:
Initial velocity (u) = 60 m/s
Height (h) = 100 m
Acceleration due to gravity (g) = 10 m/s²
Final velocity (v) =?
The velocity at height 100 m can be obtained as follow:
v² = u² – 2gh (since the ball is going against gravity)
v² = 60² – (2 × 10 × 100)
v² = 3600 – 2000
v² = 1600
Take the square root of both side
v = √1600
v = 40 m/s
Thus, velocity at height 100 m is 40 m/s
