The water has an irregular surface so if the light rays fall on top then it will reflect oppositely or in some cases may refract, so the fish will seem a bit smaller or further or closer in anyway, example if u put a straw in water it looks bent but is it ? nope. So the main reason is that it refracts which makes the accuracy lesser which make it difficult.
Answer: 7291.2 joules
Explanation:
Work is done when force is applied on an object over a distance.
Thus, Workdone = Force X distance
Since Distance moved by box = 12 metres
mass of box = 62kg
Acceleration due to gravity when box was lifted is represented by g = 9.8m/s^2
Recall that Force = Mass x acceleration due to gravity
i.e Force = 62kg x 9.8m/s^2
= 607.6 Newton
So, Workdone = Force X Distance
Workdone = 607.6 Newton X 12 metres
Workdone = 7291.2 joules
Thus, 7291.2 joules of work was done.
Very high melting<span> points - Substances with giant covalent structures have very high</span>melting<span> points, because a lot of strong covalent bonds must be broken. Graphite, for example, has a </span>melting point<span> of more than 3,600ºC. Variable conductivity - Diamond does not conduct electricity.</span>
The density of the metal can be determined through the formula [n*MW]/ Na*[a^3] . substituting, we get,
<span>d = [n*MW]/ Na*[a^3]
</span><span>d = [4 atoms*42.3 g/mol]/ [6.022 x 1023atoms/mol* (sqrt 8 *1.20x10-10)^3]
</span>d = 0.719 g/cm3
Answer:
a. Temperatures increase can change a solid to a liquid, but cannot change a liquid to a solid
b. The particles in a solid are much closer together than the particles in a liquid.
Explanation:
Any material expands when heated and contracts when cooled. So, when a body is heated to a particular temperature, it starts melting and changes into a liquid.
As the material expands the distance between the atoms or molecules increases and it will become a liquid. So it can move around the material. It doesn't become solid on further heating. But water is an exception where it contracts when heated from 0° to 4° C.
In solids, these atoms or molecules are closely packed. It is rigidly fixed.
The solid, as well as the liquid, has a definite volume, but the liquid does not have a definite shape.
