a locomotive is traveling at 120 mph. the engineers reaction time is 0.9 seconds how many feet will the train travel before the engineer recognises an emergency and applies the brake.
A.265.ft
B.260.ft
C.160.ft
D.165.ft.
distance = rate x time
= (120)5280/3600 ft/s x .9 s
= 158.4 ft
To calculate the distance the locomotive will travel before the engineer recognizes the emergency and applies the brake, we need to use the formula:
Distance = Speed × Time
First, let's convert the speed from miles per hour (mph) to feet per second (fps) since the reaction time is given in seconds.
1 mile = 5280 feet
1 hour = 3600 seconds
So, 120 mph can be converted to fps as follows:
120 mph = (120 × 5280) / 3600 fps = 176 fps (approx.)
Now, we can calculate the distance the train will travel during the reaction time of 0.9 seconds:
Distance = Speed × Time
Distance = 176 fps × 0.9 seconds
Distance ≈ 158.4 feet (approx.)
Therefore, the train will travel approximately 158.4 feet before the engineer recognizes the emergency and applies the brake.
Among the answer choices provided:
A. 265 ft
B. 260 ft
C. 160 ft
D. 165 ft
The closest option to the calculated distance is C. 160 ft.