Answer:
=1.068 ×10⁻¹³N
Explanation:
Force of gravity =Gm₁m₁/d² where G is the universal gravitation constant =G = 6.673 x 10-11 N m²/kg², m₁ and m₂ is the mass of object 1 and 2 respectively and d is the distance between them. First we change the distance into SI units i.e meters 25 km= 25000 m
F= (6.673 x 10⁻¹¹ N m²/kg²×1000 kg×1000 kg)/ (25000 m)²
=1.068 ×10⁻¹³N
The general properties of solids reflect the orderly arrangement of their particles and the fixed locations of their particles.
Evaporation condensation transpiration precipitation
Emily, come to papa
Answer:
A) False
B) True
C) True
D) True
Explanation:
A) False. If the charge of the atom is +2 means that you have two protons more than number of electrons. If you have 36 electrons you must have <em>38 protons.</em> Also, the electrons are not in the nucleus.
B) True. The isotope of X contains 38 protons, two more than the electron number.
C) True. The mass number is the number of protons + number of neutrons.
If the mass number is 79 and there are 38 protons you must have 41 neutrons.
D) True. You can now the identity of the atom with the number of protons that is the same than atomic number. The strontium, Sr, is the atom with 38 as atomic number.
I hope it helps!
The answer is 1/16.
Half-life is the time required for the amount of a sample to half its value.
To calculate this, we will use the following formulas:
1.

,
where:
<span>n - a number of half-lives
</span>x - a remained fraction of a sample
2.

where:
<span>

- half-life
</span>t - <span>total time elapsed
</span><span>n - a number of half-lives
</span>
So, we know:
t = 10 min
<span>

= 2.5 min
We need:
n = ?
x = ?
</span>
We could first use the second equation to calculate n:
<span>If:

,
</span>Then:

⇒

⇒

<span>
</span>
Now we can use the first equation to calculate the remained fraction of the sample.
<span>

</span>⇒

<span>⇒

</span>