<h2>Answer: A solid mass</h2>
The first atomic model was the one proposed by Jhon Dalton, according to which it is postulated that:
"Matter is made up of <u>indivisible, indestructible and extremely small particles</u> called atoms."
That is, <em>the atom is a </em><u><em>solid and indivisible mass</em></u><em>.</em>
However, over time <u>some limitations were found in Dalton's atomic model </u>and was replaced by the Thomson's atomic model, then by Rutherford's, Bohr's, Sommerfield's, and finally Shrodinger's.
Currently it is known that each atom is composed of a nucleus and one or more electrons attached to the nucleus, which is composed of one or more protons and typically a similar number of neutrons.
In addition, the atomic nucleus is the central part of the atom and concentrates most of the total mass of the atom.
Therefore, the correct option is A.
Answer:
Explanation:
1) True. The stored energy (U) is proportional to the electric field strength (E). The electric field strength decreases when a dielectric is introduced hence inserting a dielectric decreases U.
2) False. From the formula
, capacitance is inversely proportional to distance hence if the distance is doubled, capacitance decreases.
3) False. As the distance between the electric field and the object increases, its electric field decreases.
4) False. If a dielectric is inserted, the plates are further separated. Q stays the same.
5) True. The electric field strength decreases when a dielectric is introduced and capacitance is inversely proportional to electric field hence Inserting a dielectric increases C
6) True. If a dielectric is inserted, the plates are further separated. Q stays the same.
7) True. When the distance is doubled, U increases
The mass of the seashell suspended by the two strands of spider silk is 0.28 kg.
The given parameters:
- <em>Tension on each strand of silk, T = 1.42 N</em>
- <em>Angle of inclination of each strand, θ = 75⁰</em>
The mass of the seashell at equilibrium is calculated by applying Newton's second law of motion;

where;
- W is the weight of the seashell
The weight of the seashell is calculated as;

The mass of the seashell is calculated as follows;

Thus, the mass of the seashell suspended by the two strands of spider silk is 0.28 kg.
Learn more about equilibrium forces here: brainly.com/question/8045102
Answer:
(a) The angular displacement of the toy is 18.85 rad.
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(b) The toy's angular velocity is 6.284 rad/min.
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(c) if the counterclockwise rotation is in negative direction, the angular acceleration will be positive when the toy is turned off and vice versa.
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