Answer:112.82 m/s
Explanation:
Given
range of arrow=68 m
as the arrow travels it acquire a vertical velocity 
-------1
Range is given by
R=ut
where u=initial velocity
substitute the value of t in eqn 1
--------2
and 
substitute it in 2
u=112.82 m/s
Answer:
Stable atom
Explanation:
A stable atom is one that has a balanced nuclear inter-particle force reaction as such the binding energy of a stable atom is sufficient to permanently keep the nucleus as one unit. Examples of a stable atom are the atoms of monoisotopic elements such as fluorine, sodium, iodine, gold, aluminium, and cobalt.
In a stable atom the expected number of proton, neutron, and electron are present while in an unstable atom or radioactive atom, there are more than the expected number of neutrons or protons, such that the internal energy of the nucleus is excessive and more than the binding energy, which can lead to radioactive decay.
It is 10.20 m from the ground.
<u>Explanation:</u>
<u>Given:</u>
m = 0.5 kg
PE = 50 J
We know that the Potential energy is calculated by the formula:
where m is the is mass in kg; g is acceleration due to gravity which is 9.8 m/s and h is height in meters.
PE is the Potential Energy.
Potential Energy is the amount of energy stored when an object is stationary.
Here, if we substitute the values in the formula, we get
50 = 0.5 × 9.8 × h
50 = 4.9 × h
h = 10.20 m
The miracle year for Albert Einstein was the year 1905 within which he published so many renowned papers.
<h3>When was Einstein miracle year?</h3>
The miracle year for Albert Einstein was the year 1905 within which he published so many renowned papers in a short time and became very popular.
His mindset in that year was one that challenged the orthodox explanations and sought to think outside the box.
Learn more about Albert Einstein:brainly.com/question/2964376
#SPJ1
