To solve this problem we will begin by applying the given relations of density in terms of mass and volume, and from this last value we will take its geometric measurement for a sphere (Approximation of a planet) From there we will find the radius of the planet. Finally we will make a comparison between the radius of the new planet and the radius of the earth to understand its proportion.
Defining the Volume variables we have to
Here
V= Volume
m = mass
=Density
For a spherical object the Volume is
PART A)
Equation we have
In this case the mass of new planet is 5.5times the mass of Earth,
Then,
The mass of the Earth is kg and the density is ,
Replacing we have that,
Therefore the radius of this new planet is
PART B) The value of radius of the Earth is
Then the relation between them is
Therefore the radius of the new planet in terms of radius of the Earth is
Answer: A.
Explanation: Roughly 180 - 200 million years ago, just before the first dinosaurs evolved. Mammals themselves evolved from a group or reptiles which exhibited mammal-like traits. One of them was specialized teeth. Reptiles tend to have teeth all the same shape. The mammal-like reptiles evolved tiny teeth in front of the jaw and two pairs of over sized fangs along the the sides. Like modern mammals, the head was large in proportion to the rest of the body. The jaws were also evolving another mammal trait, the ability to move sideways. Despite the lack of specialized teeth, acute hearing and the ability to chew, the dinosaurs evolved an adaptation which made them far more successful than mammals--modified leg bones. These limbs could be articulated directly under their bodies. This enabled the legs to support more weight, since the limbs were now under the body instead of at the sides. Then dinosaurs did something which secured their dominance for the next 120 million years - they began to stand on two legs. Although the back was still parallel to the ground, running on two legs greatly increased the dinosaur's speed. Mammals could simply not compete with swift, giant predators and were forced to remain small, and most became nocturnal to evade dinosaurs which were probably active during the day. Despite that they managed to survive which allowed the further evolution of mammals into us, humans.
a) gia tốc = vf-vi / t
a = 14-10 / 20
a = 0,2ms⁻²
b) dưới dạng a = Δv / t
v = lúc
v = 0,2 × 40
v = 8ms⁻¹
như v = d / t
do đó d = vt
d = 8 × 40
d = 320m
hãy đánh dấu là trí óc nhất
Answer:
The charge that passes through the starter motor is .
Explanation:
<u>Known Data</u>
- Avogadro's Number
- Current,
- Charge in an electron,
- Time,
- Diameter,
- Transversal Area,
- Volume,
<u>First Step: Find the number of the electrons per unit of volume in the wire</u>
We use the formula .
<u>Second Step: Find the drag velocity</u>
We can use the following formula
Finally, we use the formula .