Answer:
89.6 cm
Explanation:
From the question,
Volume of the rectangular object = Mass/Density.
V = m/D.................. Equation 1
Given: m = 1.278 kg, D = 4.98 g/cm³ = 4980 kg/m³
Substitute into equation 1
V = 1.278/4980
V = 2.57×10⁻⁴ m³.
But,
V = lwh............... Equation 2
Where l = length of the rectangular object, w = width of the rectangular object, h = height of the rectangular object.
make h the subject of the equation
h = V/lw........... Equation 3
Given: V = 2.57×10⁻⁴ m³, l = 0.047 m, w = 0.061 m.
Substitute into equation 3
h = 2.57×10⁻⁴/(0.047×0.061)
h = 0.896 m
h = 89.6 cm
Answer:
B- He is correct. Evaporation is a physical change, but dissolving salt in water is a chemical change. The change in mass is evidence that a chemical change occurred.
Explanation: Dissolving Salt in water is a Chemical Change, Because the Salt arrangement is different in solid state than dissolved in water. As we can see in the image below, once the Salt is dissolved, it is separated into its ions, Na+ and Cl- Now, The evaporation process is a physical change, because the water doesn´t change its configuration H20 and it only changes its form, as we can see in the image below.
A small dense centre that has a positive charge and is surrounded by moving electrons is called an Atomic Nucleus.
Answer:
The law of inertia relates to revolution of planets round the sun due to constant motion of the planets round the sun.
Explanation:
Law of inertia states that a body at rest or uniform motion will continue to be at rest or uniform motion unless it is acted upon by an external force.
The gravitational force keeps the planets revolving round the sun in a uniform motion, this will continue till infinity unless equal and opposite force acts on our planets.
Therefore, the law of inertia relates to revolution of planets round the sun due to constant motion of the planets round the sun.
