Answer:
Friction force is independent of the direction of the contacting surfaces
Explanation:
It can go any way depending on how much force is being out on it.
Before Pluto was discovered, it was predicted. Astronomers had observed that massive objects can affect the orbits of its neighbors, and, after seeing deviations in the orbits of Uranus and Neptune, assumed something substantial existed beyond their orbits.
When Pluto was spotted, it was thought to be the predicted object and was identified as a ninth planet.
A few decades later, astronomers started discovering more and more objects around other stars and didn’t know whether to call them planets or not. There appeared to be a need to define what a planet means, and that led to what some people consider Pluto’s demotion to a dwarf planet.
The International Astronomical Union decided that full-sized planets must orbit the sun, have a round shape, and have cleared their orbits of other objects. Pluto fulfills the first two criteria, but not the third.
It still goes around the sun, it’s round enough, it’s got moons, and behaves like a planet, but the idea is that Pluto did not form the same way as the rest of the planets. Pluto’s orbit is both eccentric and inclined more than the rest of the planets by about 17 degrees. That’s suggests something is different about this object.
This debate about whether to call it a planet or not is silly, because it doesn’t matter to Pluto what you call it. It is an interesting object, goes around the sun, and shows geology and an atmosphere.
There’s a tendency to define objects based on what they are now, but nothing is constant in the universe. There are some issues with the nomenclature, and a definition today may not apply to the same object tomorrow.
When a plane travels 395,000 meters in 9,000 seconds its speed is 395,000 ÷ 9000 = 43.888888 (the 8 repeats) meters per second.
Answer:
v = 6.06 m/s
Explanation:
In order for the rider to pass the top of the loop without falling, his weight must be equal to the centripetal force:
where,
v = minimum speed of motorcycle at top of the loop = ?
g = acceleration due to gravity = 9.8 m/s²
r = radius of the loop = diameter/2 = 7.5 m/2 = 3.75 m
Therefore, using these values in equation, we get:
<u>v = 6.06 m/s</u>
