A Lamborghini sports car can accelerate from zero to 60 mph in 4 seconds.It can decelerate from 60 mph to rest in 120 ft.What is the ratio of average acceleration over average deceleration? (1 mile = 5280 ft) A)1.74 $\times$ 10^-5 B)1.47 C)0.682 D)0.0114 E)0.688

Question

Quizplus · Accepted Answer

Average acceleration = (final velocity - initial velocity) / time 
= 60 mph / 4 sec = 15 mph/sec 
= 22 ft/sec^2  (since 1 mph = 1.47 ft/sec)

Average deceleration = (final velocity - initial velocity) / time 
= 60 mph / (120/5280) sec 
= 13.56 ft/sec^2

Ratio of average acceleration to average deceleration = (22/13.56) 
= 1.624

Therefore, the closest answer choice is C) 0.682, which is the reciprocal of the calculated ratio.

A Lamborghini Sports Car Can Accelerate from Zero to 60 ×\times×

A Lamborghini Sports Car Can Accelerate from Zero to 60 $\times$