Answer:
42.87
Explanation:
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420/9.8 which equals 42.87.
Answer:
The angle of incidence is greater than the angle of refraction
Explanation:
Refraction occurs when a light wave passes through the boundary between two mediums.
When a ray of light is refracted, it changes speed and direction, according to Snell's Law:
where
:
is the index of refraction of the 1st medium
is the index of refraction of the 2nd medium
is the angle of incidence (the angle between the incident ray and the normal to the boundary)
is the angle of refraction (the angle between the refracted ray and the normal to the boundary)
In this problem, we have a ray of light passing from air into clear plastic. We have:
(index of refraction of air)
approx. (index of refraction in clear plastic)
Snell's Law can be rewritten as
And since , we have
And so
Which means that
The angle of incidence is greater than the angle of refraction
Answer: The level of CO2 has risen.
Explanation:
From the table shown, we can see that the quantity of CO₂ in the atmosphere has steadily risen since the year 1960 going from 317 CO₂PPM in that year to 390 CO₂PPM in 2010.
This is a cause for alarm because with so much carbon dioxide in the atmosphere, there will be an even greater greenhouse effect that will contribute to global warming.
Answer:
d. 37 °C
Explanation:
= mass of lump of metal = 250 g
= specific heat of lump of metal = 0.25 cal/g°C
= Initial temperature of lump of metal = 70 °C
= mass of water = 75 g
= specific heat of water = 1 cal/g°C
= Initial temperature of water = 20 °C
= mass of calorimeter = 500 g
= specific heat of calorimeter = 0.10 cal/g°C
= Initial temperature of calorimeter = 20 °C
= Final equilibrium temperature
Using conservation of heat
Heat lost by lump of metal = heat gained by water + heat gained by calorimeter
Thermal energy is transforming, i think.