Answer: f=150cm in water and f=60cm in air.
Explanation: Focal length is a measurement of how strong light is converged or diverged by a system. To find the variable, it can be used the formula:
= (nglass - ni)(
- 
).
nglass is the index of refraction of the glass;
ni is the index of refraction of the medium you want, water in this case;
R1 is the curvature through which light enters the lens;
R2 is the curvature of the surface which it exits the lens;
Substituting and calculating for water (nwater = 1.3):
= (1.5 - 1.3)(
- 
)
= 0.2(
)
f = 
= 150
For air (nair = 1):
= (1.5 - 1)( - )
f = 
= 60
In water, the focal length of the lens is f = 150cm.
In air, f = 60cm.
Answer:
The average velocity is 7.5 km/h
Explanation:
Let's convert minutes to hours so our answer can be given in a common units of km/hour:
12 minutes = 12/60 hours = 0.2 hours
Now we estimate the average velocity calculating the distance travelled over the time it took:
1.5 / 0.2 km/h = 7.5 km/h
Answer:
i am answering the same question 3rd time
please find the answer in the images attached.
The correct option is D.
The model developed by Ptolemy has a lot of inconsistency and during the middle age additional explanation was offered for the claims made by the model. The model was very complicated because it was based on erroneous assumptions.
Copernicus model was simpler and some of his claims were correct.<span />
The kinetic energy of any moving object is
(1/2) (mass) (speed²) .
For the object you described, that's
(1/2) (100 kg) (12.5 m/s)²
= (50 kg) (156.25 m²/s²)
= 7,812.5 joules
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Your attachment is way out of focus, and impossible to read.
