Respuesta :
A) the velocity at the end of the time is 1.5 m/s
B)the total distance traveled is 4.2 meters
Explanation
Velocity is the rate at which the position changes,and acceleration is the rate of change in velocity over time
the acceleration can be calculated usign the expression:
[tex]a=\frac{\Delta velocity\text{ }}{\Delta\text{ time}}=\frac{v_f-v_i}{\text{t}}[/tex]Step 1
A. What is his velocity at the end of the time?
we need to use the formula
[tex]\begin{gathered} v_f=v_i+at \\ where \\ v_i\text{ is the initial velocity} \\ a\text{ is the acceleration } \\ t\text{ is the time} \end{gathered}[/tex]so, replace
[tex]\begin{gathered} v_f=v_i+at \\ v_f=5+(-1.2\frac{m}{s^2})(3\text{ s)} \\ v_f=(5-3.6\text{ )}\frac{m}{s^{}} \\ v_f=1.4\frac{m}{s^{}} \end{gathered}[/tex]so, the velocity at the end of the time is 1.5 m/s
Step 2
What distance does he travel during the whole process :
to find this we need use the equation :
[tex]d=v_1t+\frac{1}{2}at^2[/tex]so,let
[tex]\begin{gathered} v_i=5\text{ }\frac{m}{s} \\ t=\text{ 3 s} \\ a=-1.2\frac{m}{s^2} \end{gathered}[/tex]replace
[tex]\begin{gathered} d=v_1t+\frac{1}{2}at^2 \\ d=(5\text{ }\frac{m}{s})(3\text{ s)+}\frac{1}{2}(-1.2\frac{m}{s^2})(3s)^2 \\ d=15\text{ m-}10.8\text{ m} \\ d=4.2\text{ m} \end{gathered}[/tex]so
the total distance traveled is 4.2 meters
I hope this helps you
