Answer:
PE = 44.1 J
Explanation:
Ok, to have the specific data, the first thing we must do is convert from grams to kilograms. Since mass must always be in kilograms (kg)
We have:
- 1 kilograms = 1000 grams.
We convert it using a rule of 3, replacing, simplifying units and solving:
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Earth's gravity is known to be 9.8 m/s², so we have:
Data:
- m = 0.3 kg
- g = 9.8 m/s²
- h = 15 m
- PE = ?
Use formula of potencial energy:
Replace and solve:
Since the decimal number, that is, the number after the comma is less than 5, it cannot be rounded, then we have this result.
The potential energy of the volleyball is <u>44.1 Joules.</u>
Greetings.
Answer:
Cat and a dog
Explanation:
The cat might bark instead of meow because it has certain traits from the dog. The dog however may still bark because it is a dog!
The answer to this question is B, Reacts with sunlight.
The 2 main properties of substances are their physical properties and chemical properties.
Physical properties are some observable/measurable characteristics, such as their color, mass, state, melting point, conductivity etc.
Meanwhile, for chemical properties, they're about how the substance reacts with other substances, such as metals react with acid to form hydrogen. And by the word "react", it means there's no way turn the reaction product back to the original substance without using chemical methods such as heating or electrolysis.
Therefore, all the choices above are physical properties of hydrogen peroxide except for B, as it is the only choice that relates to the substance reacting to another substance.
According to the conservation of mechanical energy, the kinetic energy just before the ball strikes the ground is equal to the potential energy just before it fell.
Therefore, we can say KE = PE
We know that PE = m·g·h
Which means KE = m·g·h
We can solve for h:
h = KE / m·g
= 20 / (0.15 · 9.8)
= 13.6m
The correct answer is: the ball has fallen from a height of 13.6m.