Explanation:
If both distance and size are proportional to that in the solar system, the model would be essentially useless.
For example, if the sun were represented by a marble 1 cm in diameter, the planet Neptune would be represented by a grain of sand .3 mm in diameter about 32.3 meters (106 ft) away. The largest planet, Jupiter, would be a larger sand grain, 1 mm in diameter, about 5.6 meters from the sun. Earth would be less than 0.1 mm in diameter, about 1 meter away from the sun.
Such a model would barely fit into a gymnasium (basketball court), and the elements of it would be very difficult to find without a map.
Answer:
do explain what u need help with?
Answer:
3.456 × 10⁻⁴³ J
Explanation:
The work done in bringing two charges q₁ and q₂ separated by a distance, r together is W = kq₁q₂/r. With the first charge q₁ in place, the work done in bringing the second charge into the vertex of the equilateral at a distance, r is W₁₂ = kq₁q₂/r. Since the first and second charges are in place, the work done in bringing the third charge q₃ in place is work done W₁₃ between q₁ and q₃ = kq₁q₃/r plus work done W₂₃ between q₂ and q₃ = kq₂q₃/r. So the total work done in assembling the atomic nucleus is W = W₁₂ + W₁₃ + W₂₃ = kq₁q₂/r + kq₁q₃/r + kq₂q₃/r. Since q₁ = q₂ = q₃ = q = 1.6 × 10⁻¹⁹ C, W = 3kq²/r. Since r = side of equilateral triangle = 2.0 × 10⁻¹⁵ m. W = 3 × 9 × 10⁹ × (1.6 × 10⁻¹⁹)²/2.0 × 10⁻¹⁵ = 3.456 × 10⁻⁴³ J ≅ 3.46 × 10⁻⁴³ J
Radioactivity is a part of our earth - it has existed all along. Naturally occurring radioactive materials are present in its crust, the floors and walls of our homes, schools, or offices and in the food we eat and drink. There are radioactive gases in the air we breathe. Our own bodies - muscles, bones, and tissue - contain naturally occurring radioactive elements.