Answer: False
Explanation: The sun is one of earths primary energy sources. Without the sun, all animals, plants, humans would die. The sun's energy provides warmth for humans and plants and animals cannot grow without the sun.
Answer:
U₁ = 129.4 J
Explanation:
The potential energy is
U = mg y - m g y₀
Where I correspond to the initial position, with this it is an additive constant, we can make it zero with the placement of the reference system, in this case the system is placed on the floor where the ladder rests.
The power power for people on the floor is
U₀ = 0 J
The potential energy for the person on the first step is
U₁ = m g y₁
In general the steps are 20 cm high
y₁ = 20 cm (1m / 100cm) = 0.20 m
U₁ = 66 9.8 0.20
U₁ = 129.4 J
A pure substance contain only a single type of molecule
The grape absorbs all colors except green, and green light is the
only light that remains to bounce around and enter people's eyes.
This is a big part of the reason why, whenever somebody looks at
the grape, they remark "Oh look ! The grape is green !"
Answer:
Acid is any substance from 0-6
(stomach acid, lemon juice, vinegar, milk, soda, rainwater)
Bases are any substance from 8-14
(egg whites, baking soda, ammonia)
Neutral are 7
(pure water)
Explanation:
* Acids taste sour, are corrosive to metals, change litmus (a dye extracted from lichens) red, and become less acidic when mixed with bases.
* Bases feel slippery, change litmus blue, and become less basic when mixed with acids.
