1.5kj of energy are used every second by a microwave oven, what is the power rating of the oven?
2 answers:
Power is the rate at which energy is consumed. When 1 J of energy is consumed in one second, the power consumed is 1 watt.
The microwave consumes 1.5 kJ of energy.
In joules, the energy consumed is 1500 J
Here, E is the energy consumed in time interval <em>t.</em>
The power rating of the microwave is therefore,
Thus, the power rating of the oven is 1500 W or 1.5 kW
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Explanation:
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speed of boat
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therefore frequency of the echo slightly decreased.
1. Protons and neutrons have the same charge.
Protons have positive charge, equal to , while neutrons have zero charge.
2. mass number
The mass number of an atom is equal to the sum of protons and neutrons inside its nucleus.
3. Atoms are made up of smaller particles.
According to Dalton's theory, atoms are the smallest particles that make matter, and they are indivisible and indestructible, so they are NOT made up of smaller particles.
4. a solid sphere
In Dalton's theory, atoms are not made of smaller particles, so we can think them as solid spheres.
5. J. J. Thomson
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6. An electron has the same amount of energy in all orbitals.
In fact, each orbital corresponds to a different energy level: the farther the orbital from the nucleus, the higher the energy of the electrons contained in that orbital.
7. A hydrogen atom in heavy water has an extra neutron.
Heavy water is a type of water that contains deuterium, which is an isotope of the hydrogen consisting of one proton and one neutron (so, one extra neutron).
8. The glowing beam was always deflected by charged plates
In his cathode's ray tube experiment, Thomson shows that the beam of unknown particles (= the electrons) were deflected by charge plates, so the particles had to be also electrically charged.
9. electrons move to a lower energy level
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10. orbital
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11. 14
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12. negative charge, found outside the nucleus
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13. move from higher to lower energy levels
When electrons move from a higher energy level to a lower energy inside a neon atom, they emit a photon (which is light) whose energy is equal to the difference in energy between the two energy levels.
14. atomic number from its mass number
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- the atomic number of an atom (Z) is equal to the number of protons inside the nucleus
- the mass number of an atom (A) is equal to the sum of protons+neutrons inside the nucleus
Therefore, we can find the number of neutrons in the nucleus by calculating the difference between A and Z:
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15. None of them
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