<h2>Answer: Gravitational attraction
</h2>
Gravity force causes the clouds of dust and gas to form a protostar. As this <u>attraction force</u> is responsible for gathering and compressing the existing elements in the cloud of gas and dust, heating them during this process.
Then, when the amount of material accumulated by gravitational contraction is large enough, and the temperature and pressure reached high enough, the <u>nuclear fusion</u> process will begin.
To understand it better: The hydrogen nuclei will begin to fuse, generating helium nuclei in the process and releasing huge amounts of energy.
It should be noted that the protostars radiate half of the energy contributed by the gravitational collapse and the other half is invested in heating its core.
Answer: A
Explanation:
honestly, it sounded the best
Answer:
<em>The final speed of the second package is twice as much as the final speed of the first package.</em>
Explanation:
<u>Free Fall Motion</u>
If an object is dropped in the air, it starts a vertical movement with an acceleration equal to g=9.8 m/s^2. The speed of the object after a time t is:

And the distance traveled downwards is:

If we know the height at which the object was dropped, we can calculate the time it takes to reach the ground by solving the last equation for t:

Replacing into the first equation:

Rationalizing:

Let's call v1 the final speed of the package dropped from a height H. Thus:

Let v2 be the final speed of the package dropped from a height 4H. Thus:

Taking out the square root of 4:

Dividing v2/v1 we can compare the final speeds:

Simplifying:

The final speed of the second package is twice as much as the final speed of the first package.
Answer:
- <u>2.79 N</u>
- <u>8.34 N</u>
- <u>Watermelon</u>
Explanation:
<u>Weight of soccer ball</u>
- Weight = mass (in kg) × gravitational force
- Weight = 284 x 10⁻³ x 9.81
- Weight = 0.284 x 9.81
- Weight = <u>2.79 N</u> (approximately)
<u>Weight of watermelon</u>
- Weight = mass (in kg) x gravitational force
- Weight = 850 x 10⁻³ x 9.81
- Weight = 0.85 x 9.81
- Weight = <u>8.34 N</u> (approximately)
As the <u>watermelon</u> has more weight, it will hit the ground first.
v2 = ?
m1 = 10kg
m2 = 70kg
v1 = 4m/s
E1 = E2
E1 = 1/2 * m1 * v1^2 = 1/2 * 10kg * 4m/s^2 = 80J
E2 = 1/2 * m2 * v2^2 = 80 J
v2 = √(E2/(2 * m2)) = √(80J/(2 * 70kg)) = about 0.76m/s