(4) The average diameter of an atom's nucleus is about \( 1 \times 10^{-14} \) meter. The diameter of a proton is about \( 1 \times 10^{-15} \) meter. (4) Which is larger, the diameter of a nucleus or the ediameter of a proton?

Class 7 th Science Paper School Based Assessment 2024 I SBA First Term pape Explain why an atom is an electrically neutral particle and give one example. Model answer: The number of positively charged protons present in an atom is equal to the number of negatively charged electrons present there. It means that the total positive charge on an atom (due to protons) is equal to the total negative charge on it (due to electrons). The equal amounts of positive and negative charges cancel the effect of each other. An atom is therefore electrically neutral particle. Example: The neon atom is electrically neutral.

Solve the equation. \[ \begin{array}{l}2-10 n+5 n=3-76\end{array} \]

(6) \( \frac{5}{6} \) yard for 4 dresses

\( 3(-4+4)-(5-11) \) \( 3(-4+4)-(5-11)=\square \) (Type an integer or a fraction.)

Suppose that \( \ln 3=r \) and \( \ln 7=s \). Use properties of logarithms to write the logarith terms of \( r \) and \( s \). \( \ln 21 \) \( \ln 21=\square \)