Question

. A car increases its speed from 20 km/h to 30 km/h in 10 seconds. Its acceleration is...
a. 30 m/s2
b. 3 m/s2
c. 18 m/s2
d. 0.83 m/s2

Answer 1

HELLO THERE!

This is a very simple question, and can be done using the Equations of motion.

Given data:

u (initial speed) = 20 km/h = 20 x 5/18 m/s = 5.56 m/s

v (final speed) = 30 km/h = 30 x 5/18 m/s = 8.33 m/s

Time (t) = 10 seconds.

v = u + at

=> 8.33 = 5.56 + 10a

=> 10a = 8.33 - 5.56

=> 10a = 2.77

=> a = 0.277 m/s²

This is the correct answer. The answers given in options are not matching.