Answer:
Average speed of the car during the motion is 3.5 m/s
Explanation:
Distance covered with speed v1 = 3 m/s for t1 =20 s is
[tex]x_{1}= vt\\x_{1}=3 \times 20\\x_{1}=60 m[/tex]
Distance covered with speed v2 = 4 m/s for t2 =20 s is
[tex]x_{2}= vt\\x_{1}=4 \times 20\\x_{1}=80 m[/tex]
Average speed = total distance covered / total time taken
[tex]V_{avg} = \frac{x_{1}+x_{2}}{t_{1}+t_{2}} \\\\V_{avg} = \frac{60+80}{20+20} \\\\V_{avg}=3.5 m/s[/tex]
Average speed of the car during the motion is 3.5 m/s