Question

The position of an object change from r= (2i+j) to r=(4i+3j) in 2s find average velocity

Answer 1

First we need to determine what the displacement will be in this case.
We can determine the displacement using the distance formula studied in 10th.

distance between two points= $((x_{2}- x_{1})^{2} + (y_{2}- y_{1})^{2})^{1/2}$

In this case,
 displacement= $((4-2)^{2} + (3-1)^{2})^{1/2}$
s=$((2)^{2} + (2)^{2})^{1/2}$
s=$(4+4)^{1/2}$
s=$(8)^{1/2}$
Therefore, s= $2(2)^{1/2}$

Now, average velocity= displacement/time
v=$\frac{2(2)^{1/2}}{2}$
Therefore,
 v=$\sqrt{2}$

Answer 2

average velocity = ∆v/∆t= 2i+j - 4i + 3j/2

=i+j

v=√1^2+1^2

= √1+1

= √2.