I'm having problems with this:
Compare the trajectory of a planet and a comet.
Planet is usually a pretty round elliptical orbit, often almost circular, around a star.
A comet may go entirely beyond the planets and then come close to the sun again. The orbit is likely to be a skinny (highly eccentric) ellipse with the focus at the sun far from the other focus of the ellipse.
i don't really know how to balance a reaction 2C2H2(g)----> fCO2(g)+______?
To compare the trajectories of a planet and a comet, you need to understand a few key concepts about these celestial objects and their motions.
1. Orbital Paths: Planets and comets follow different orbital paths around the Sun. Planets travel in nearly circular orbits around the Sun, staying close to a fixed plane called the ecliptic. Comets, on the other hand, follow more elongated elliptical paths that can take them much farther away from the Sun.
2. Eccentricity: The eccentricity of an orbit determines how elongated or circular it is. Planets typically have low eccentricities, close to 0, which means their orbits are almost circular. Comets, on the other hand, have much higher eccentricities, often close to 1, resulting in highly elongated orbits.
3. Speed: Planets generally move at a relatively constant speed along their orbits, while comets experience significant changes in speed depending on their distance from the Sun. Comets move slowly when they are farther away from the Sun and accelerate as they approach it.
4. Periodicity: Planets have much longer orbital periods, meaning it takes them many years to complete one revolution around the Sun. Comets, on the other hand, have much shorter periods, ranging from a few years to several centuries, depending on the comet.
Now, having understood these key differences, let's compare the trajectories of a planet and a comet:
1. Shape of the Orbit: The orbit of a planet is close to a circular shape, while the orbit of a comet is highly elongated, resembling an elongated elliptical path.
2. Distance from the Sun: A planet usually maintains a relatively constant distance from the Sun, whereas comets can travel much farther away from the Sun during their elongated orbits.
3. Speed: Planets move at a relatively constant speed throughout their orbits, while comets have varying speeds, slowing down as they move away from the Sun and accelerating as they get closer.
4. Frequency: Planets have much longer orbital periods, taking years to complete one orbit. Comets have shorter, more variable periods, ranging from a few years to centuries.
In summary, the trajectories of planets and comets differ in terms of their orbital shapes, distances from the Sun, speeds, and periodicity. Planets have nearly circular orbits, while comets have elongated elliptical orbits. Planets stay relatively close to the Sun, whereas comets can venture much farther away. Additionally, planets move at a steady speed, while comets experience varying speeds. Finally, planets have longer orbital periods compared to comets.