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Eva8 [605]
3 years ago
13

Also need help with 20 & 21 please

Physics
2 answers:
SSSSS [86.1K]3 years ago
5 0
Number 20 is B and 21 is C
Hoochie [10]3 years ago
5 0
A density is a physical change
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Two charged objects, A and B, are exerting an electric force on each other. What will happen if the charge on A is increased?
ozzi

Answer: The forces acting on both of them will increase in magnitude.

Explanation:

According to Coulomb's law, the electrostatic force between two bodies is proportional to the product of their two charges. If the charge on A is increased this product increases in size (it must have been non-zero to begin with, since there was a force between them at first). Thus, the force between them rises.

6 0
3 years ago
Which process is the most scientifically plausible explanation for how the organisms released oxygen into Earth's atmosphere? Gr
Stels [109]

Answer:

Photosynthesis

Explanation:

Studies about the time period of oxygen accumulation suggests that free oxygen was first produced by prokaryotic and then later by eukaryotic organisms in the ocean. These organisms carried out photosynthesis more efficiently, producing oxygen as a waste product.

The organism mainly responsible for this is known as cyanobacteria, or blue-green algae. These microbes conduct photosynthesis: using sunshine, water and carbon dioxide to produce carbohydrates and, oxygen.

8 0
4 years ago
A pebble is thrown into the air with a velocity of 19/m at an angle of 36 with respect to the horizontal.
kow [346]

Answer:

The maximum height the pebble reaches is approximately;

A. 6.4 m

Explanation:

The question is with regards to projectile motion of an object

The given parameters are;

The initial velocity of the pebble, u = 19 m/s

The angle the projectile path of the pebble makes with the horizontal, θ = 36°

The maximum height of a projectile, h_{max}, is given by the following equation;

h_{max} = \dfrac{\left (u \times sin(\theta) \right)^2}{2 \cdot g}

Therefore, substituting the known values for the pebble, we have;

h_{max} = \dfrac{\left (19 \times sin(36 ^{\circ}) \right)^2}{2 \times 9.8} = 6.3633894140470403035477570509439

Therefore, the maximum height of the pebble projectile, h_{max} ≈ 6.4 m.

3 0
3 years ago
Where on Earth​ might you find these conditions?
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Which conditions I think you have place an incorrect image?
5 0
3 years ago
1. Why does Earth's moon have no atmosphere
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1. Earth's moon has no atmosphere because the moon's gravity is too weak to hold onto gas molecules.
2. On the moon, maria are low flat plains. The word maria comes from the Latin word mare, which means sea.
7 0
3 years ago
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