91影视

The magnitude of$\stackrel{鈫�}{d}$ is 2.5 m and direction is towards north.

Vectors can be multiplied by the scalars. If we multiply the vectors by positive scalar, the direction will be same. If we multiply vectors with negative scalar, the direction will be reversed.

Formula:

$\stackrel{鈫�}{A}=n路\stackrel{鈫�}{d}$(A would be in the same direction of d but n times greater)

$\stackrel{鈫�}{A}=\left(-n\right)路\stackrel{鈫�}{d}$(A would be n times greater than d but opposite in the direction of d)

Use the given value of the magnitude of vector $\stackrel{鈫�}{d}$to calculate the magnitude of role="math" localid="1660888706506" $4.\stackrel{鈫�}{d}$

$\begin{array}{rcl}\left|4路\stackrel{鈫�}{d}\right|& =& 4路\left|\stackrel{鈫�}{d}\right|\\ & =& 4脳2.5\text{m}\\ & & \text{= 10}\text{m}\\ & & \\ & & \end{array}$

Since, the vector is multiplied by the positive scalar, the direction will remain the same, i.e., towards north.

Use the given value of the magnitude of vector $\stackrel{鈫�}{d}$to calculate the magnitude of $-3.0\stackrel{鈫�}{d}$

$\begin{array}{rcl}\left|-3路\stackrel{鈫�}{d}\right|& =& 3路\left|\stackrel{鈫�}{d}\right|\\ & =& 3脳2.5\text{m}\\ & =& 7.5\text{m}\\ & & \end{array}$

Therefore, the magnitude of $-3.0\stackrel{鈫�}{d}$is 7.5 m.

The negative sign indicates that the direction will be opposite to the direction of $\stackrel{鈫�}{d}$. So, it will be towards south.