Question

The average velocity between $t=2.0s$ and $t=4.0s$ is:

• A. $30$
• B. $15m{s}^{-1}$
• C. $10m{s}^{-1}$
• D. None of these

Answer 1

Answer: (B)

Average velocity $=\frac{x\left(t_2\right)-x\left(t_1\right)}{t_2-t_1}$
$=\frac{x(4.0)-x(2.0)}{4.0-2.0}$
Given, $n(t)=a+b{t}^2$
$=\frac{(a+16b)-(a+4b)}{2,0}=6.0b$
$=6.0\times 2.5=15m{s}^{-1}$