1. it is difficult to search for it . Because infrared rays will never penetrate through earth atmosphere.
2. we are unaware of how it looks like and we only know it is red and will glow . A damaged star also looks like this.
3. Dust also makes is hard to detect Dyson spheres . So we will get confused between Dyson sphere and a star surrounded by dust.
I believe the correct answer from the choices listed above is option C. X-rays have greater frequency than microwaves. In a electromagnetic spectrum, the order in increasing frequency is as follows:
radio waves,microwaves, terahertz radiation, infrared radiation, visible light, ultraviolet radiation,X-rays<span> and gamma </span>rays<span>.</span>
Wow ! This is not simple. At first, it looks like there's not enough information, because we don't know the mass of the cars. But I"m pretty sure it turns out that we don't need to know it.
At the top of the first hill, the car's potential energy is
PE = (mass) x (gravity) x (height) .
At the bottom, the car's kinetic energy is
KE = (1/2) (mass) (speed²) .
You said that the car's speed is 70 m/s at the bottom of the hill,
and you also said that 10% of the energy will be lost on the way
down. So now, here comes the big jump. Put a comment under
my answer if you don't see where I got this equation:
KE = 0.9 PE
(1/2) (mass) (70 m/s)² = (0.9) (mass) (gravity) (height)
Divide each side by (mass):
(0.5) (4900 m²/s²) = (0.9) (9.8 m/s²) (height)
(There goes the mass. As long as the whole thing is 90% efficient,
the solution will be the same for any number of cars, loaded with
any number of passengers.)
Divide each side by (0.9):
(0.5/0.9) (4900 m²/s²) = (9.8 m/s²) (height)
Divide each side by (9.8 m/s²):
Height = (5/9)(4900 m²/s²) / (9.8 m/s²)
= (5 x 4900 m²/s²) / (9 x 9.8 m/s²)
= (24,500 / 88.2) (m²/s²) / (m/s²)
= 277-7/9 meters
(about 911 feet)
Weathering and rock slides
Pure water.
A salt solution contains impurities whereas pure water will not contain any impurities.
Impurities increase the boiling point (freezing point) of a substance.
Thus, I would expect the pure water solution to freeze faster than the salt solution.
