Question

Biker 1 is on a motorcycle facing West is initially at rest. The motorcycle speeds up from rest to 25 mph in three seconds.

Answer 1

Biker 1's acceleration:

(25 mph) / (3 s) = ((25 mi/h) • (1/3600 h/s)) / (3 s) ≈ 0.00231 mi/s²

Biker 2's acceleration:

(85 mph) / (8 s) = ((85 mi/h) • (1/3600 h/s)) / (8 s) ≈ 0.00295 mi/s²

Biker 2 has the greater acceleration.