Answer: object B is negatively charged, object C is positively charged and object D is also positively charged
Explanation: since unlike charges attract and like charges repel, for object A which is positively charged and B to attract B must be negatively charged and then for B which is negatively charged and C to attract C must be positively charged and for C and D to repel they have to be of thesame charge which means D is positive as well.
The equation that represents the principle of the lever balance is:
- W₁ + W₂ = W3 + W4; option A.
<h3>What is the principle of moments?</h3>
The principle of moments states when a body is in equilibrium, the sum of the clockwise moment about a point equals the sum of anticlockwise moment about that point.
A see-saw represents a balanced system of moments.
The sum of clockwise moment = The sum of anticlockwise moments.
Assuming W1 and W2 are clockwise moments and W3 and W4 are anticlockwise moments.
The equation will b: W₁ + W₂ = W3 + W4
In conclusion, a balanced see-saw illustrates the principle of the lever balance.
Learn more about principle of moments at: brainly.com/question/20519177
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20 ohms in parallel with 16 ohm= 8.89
20x16/20+16. Product over sum
Answer: Solar Energy has been helping the supplying companies to be able to hire more people for jobs which helps 12 times more easier than the US, Things like solar, geothermal, and wind can help reduce the water resources which helps to save our water conservation rate which was getting increasingly High.
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Answer:

Explanation:
Given data
Frequency f=90 Hz
To find
First three overtones of bassoon
Solution
The fundamental frequency of bassoon is found by substituting n=1 in below equation
f=v/λ=nv/2L

The first overtone of bassoon is found by substituting n=2
So
The second overtone of bassoon is found by substituting n=3
So

The third overtone of bassoon is found by substituting n=4
So
