Question

1. using a scale of 1 cm = 5 n, draw force vectors representing a +20 n force and a -10 n force.

Explanation:

Step1: Calculate the length of the +20N force vector

Since the scale is \(1\ cm = 5\ N\), for a \(F_1=+20\ N\) force, the length \(l_1\) of the vector is calculated by \(l_1=\frac{F_1}{5\ N/cm}\). Substituting \(F_1 = 20\ N\), we get \(l_1=\frac{20\ N}{5\ N/cm}=4\ cm\). Draw a vector of length \(4\ cm\) in the positive direction (e.g., to the right if we assume a horizontal axis).

Step2: Calculate the length of the - 10N force vector

For a \(F_2=-10\ N\) force, using the same scale \(1\ cm = 5\ N\), the length \(l_2\) of the vector is \(l_2=\frac{\vert F_2\vert}{5\ N/cm}\). Substituting \(F_2=-10\ N\) (we take the magnitude for length calculation), we have \(l_2=\frac{10\ N}{5\ N/cm}=2\ cm\). Draw a vector of length \(2\ cm\) in the negative direction (e.g., to the left if we assume a horizontal axis).

Answer:

Draw a \(4 - cm\) vector in the positive direction and a \(2 - cm\) vector in the negative direction according to the scale \(1\ cm = 5\ N\).