Question

A plane accelerates down a runway. The plane accelerates at 2 m/s/s for 10 seconds and obtains a speed of 20 m/s. What speed would a second plane obtain if it had double the acceleration for double the time of the first plane? A) 20 m/s B) 40 m/s C) 80 m/s D) 160 m/s

Answer 1

here acceleration initially is given as 2 m/s/s for total time of 10 s

so in above situation the final speed will be 20 m/s

now here if acceleration is double as well as the time is also double

so now we will have

$a = 4 m/s^2$

$t = 20 s$

so now the final speed is given as

$v_f = 4 (20)$

$v_f = 80 m/s$