Plate techtonics refers to the theory that

1. Which of the following does Kepler's Second Law support?

nlexa [21]

Answer:

A: When a planet is closer to the Sun, its speed is greater than when it is farther away.

Explanation:

Kepler's laws establish that:

All the planets revolve around the Sun in an elipse orbit, with the sun in one of the focus (Kepler's first law).

A planet describes equal areas in equal times (Kepler's second law).

The square of the period of a planet will be proportional to the cube of the semi-major axis of its orbit (Kepler's third law).

$T^{2} = a^{3}$

Where T is the period of revolution and a is the semi-major axis.

Since planets orbit around the Sun in an ellipse, with the Sun in one of the focus, in some moments of their orbit they will be closer to the Sun (known as perihelion). According with Kepler's second law to complete the same area in the same time, they has to speed up at their perihelion and slow down at their aphelion (point farther from the sun in their orbit).

That increase in the orbital velocity as a consequence of the distance can be prove by the Universal law of gravitation:

$F = G\frac{Mm}{r^{2}}$ (1)

Where G is the gravitational constant, M and m are the masses of the two objects and r is the distance between them.

$F = ma$ (2)

Where m is the mass and a is the acceleration. Equation (2) can be replaced in equation (1).

$ma = G\frac{Mm}{r^{2}}$ (3)

Since it is a circular motion, the centripetal acceleration is defined as:

$a_{c} = \frac{v^{2}}{r}$ (4)

Replacing (4) in (3) it is got:

$m\frac{v^{2}}{r} = G\frac{Mm}{r^{2}}$ (5)

Notice that m in equation (5) represents the mass of the planet while M is the mass of the Sun.

Equation (5) can be expressed in term of v:

$v = \sqrt{\frac{GM}{r}}$ (6)

Hence, if the distance increases the orbital velocity decreases (inversely proportional).

3 0

3 years ago

Which of the following are bases? Check all that apply. A. KOH B. NaOH C. CH4 D. HCl

Wittaler [7]

Well, the answer here is B. NaOH is Sodium Hydroxide and yes that has a very STRONG base. So this is a proven fact because, the element is held together by covalent bonds.

8 0

4 years ago

A bullet of mass m 1 is fired into a rod of length L and mass m 2 which is pivoted on one end and rests on a frictionless horizo

Reptile [31]

Answer:

The angular speed of the rod is $w=(\frac{9m_{1}v_{i} }{4m_{2}L } )(1-\frac{1}{\sqrt{2} } )$

Explanation:

The final kinetic energy is:

$\frac{1}{2} mv_{f}^{2} =\frac{1}{2}(\frac{1}{2} mv_{i}^{2} )$

Clearing vf:

$v_{f} =\frac{1}{\sqrt{2} } v_{i}$

The conservation of angular momentum before and after collision is:

$m_{1} v_{i} (\frac{3L}{4} )=Iw+m_{1}v_{f} (\frac{3L}{4} )$

Clearing w:

$w=(\frac{9m_{1}v_{i} }{4m_{2}L } )(1-\frac{1}{\sqrt{2} } )$

3 0

4 years ago

Hii:) anyone able to explain and help me with this question?

Assoli18 [71]

Answer:

No

Explanation:

The equation of state for ideal gases tells that:

$pV=nRT$

where

p is the gas pressure

V is the gas volume

n is the number of moles of the gas

R is the gas constant

T is the absolute temperature

In this problem, we have a fixed mass of gas. This means that the number of moles of the gas, $n$ , does not change; also, the volume V remains the same, and R is a constant, this means that

$p\propto T$

So, as the pressure increases, the temperature increases.

However, here we want to understand what happens to the average distance between the molecules.

We have said previously that the number of moles n does not change: and therefore, the total number of molecules in has does not change either.

If we consider one dimension only, we can say that the average distance between the molecules is

$d=\frac{L}{N}$

where L is the length of the container and N the number of molecules. Since the volume of the container here does not change, L does not change, and since N is constant, this means that the average distance between the molecules remains the same.

4 0

3 years ago

A man with a mass of 70 kg walks up a flight of stairs that is 5 m tall. Another man with a mass of 80 kg walks up the same flig

Alex_Xolod [135]

It's 'D'. You need to know the time in order to calculate power.

5 0

3 years ago