Answer:
35 J
Explanation:
The man is holding the box: this means that he is applying a force vertically upward, to balance the weight of the box (which pushes downward).
Therefore, we can ignore the horizontal displacement of the man, because the force applied (vertically upward) is perpendicular to that displacement (horizontal), so the work done for that is zero.
So, only the vertical motion contributes to the work. The work done by the man is equal to the gain in gravitational potential energy of the box, so:

where
is the weight of the box
is the vertical displacement
Substituting, we find

<span><span>Use the periodic table and your knowledge of isotopes to complete these statements.
When polonium-210 emits an alpha particle, the child isotope has an atomic mass of </span><span> ⇒ 206</span>.</span>
<span><span>I-131 undergoes beta-minus decay. The chemical symbol for the new element is </span><span> ⇒ Xe</span>.</span>
<span><span>Fluorine-18 undergoes beta-plus decay. The child isotope has an atomic mass of </span><span> ⇒ 18</span>.</span>
Answer:C
Explanation:
Mass energy of hydrogen fusing into helium
Answer:

Explanation:
As we know that water from the fountain will raise to maximum height

now by energy conservation we can say that initial speed of the water just after it moves out will be




Now we can use Bernuolli's theorem to find the initial pressure inside the pipe



Answer:
43.58 m
Explanation:
If you travel 500 m on a straight road that slopes upward at a constant angle of 5 degrees
Using trigonometry ratio
Sin 5 = opposite/hypothenus
Where the hypothenus = 500m
Opposite = height h
Sin 5 = h/500
Cross multiply
500 × sin 5 = h
h = 500 × 0.08715
h = 43.58m
Therefore, the height above the starting point is equal to 43.58m