Answer:
Explanation:
We usually approximate the density of water to about 
at room temperature. In terms of the precise density of water, this is not the case, however, as density is temperature-dependent.
The density of water decreases with an increase in temperature after the peak point of its density. The same trend might be spotted if the temperature of water is decreased from the peak point.
This peak point at which the density of water has the greatest value is usually approximated to about 
. For your information, I'm attaching the graph illustrating the function of the density of water against temperature where you could clearly indicate the maximum point.
To a higher precision, the density of water has a maximum value at , and the density at this point is exactly .
Note that the density of pure aluminum is 2.7 g/cm³ (from tables).
Given:
m = 39.0 g, the mass of the metal
V = 10.0 cm³, the density of the metal
By definition, the density of the metal is
density = mass/volume
= (39.0 g)/(10.0 cm³)
= 3.9 g/cm³
Answer:
The calculated density is not equal to 2.7 g/cm³, therefore the metal sphere is not made of pure aluminum.
Energy can be conserved by efficient energy use.
Answer: Option A
<u>Explanation:</u>
Energy can be transferred from one form to another, but it cannot be destroyed or created. So it can be conserved if efficiently used. Thus efficient usage of energy lead to conservation of energy. Due to conservation of energy, the forces can be renewable and non-renewable.
So, we should know how the input energy can be completely converted to another form of energy leading to efficient usage of energy without any loss. As if there is no loss, input energy will be equal to output energy leading to 100% efficiency.
Electrons are added to the same principal energy level.
