an automobile starts from rest and in 100 ft attains a speed of 30miles/hour. in what time has it traveled and
eyra_027 asked:
an automobile starts from rest and in 100 ft attains a speed of 30miles/hour. in what time has it traveled and what is the acceleration?
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an automobile starts from rest and in 100 ft attains a speed of 30miles/hour. in what time has it traveled and what is the acceleration?
April 13th, 2010 at 8:45 am
Conversion: 30 miles/hour = 44 feet/sec
1st step: Find the time
Speed = distance /time
44 = 100feet/t
t = 2.27 seconds.
2nd step: Find acceleration
V = Vo + at
30 = 0 +a(2.27)
30/2.27 = a
a =13.2 ft/s^2 ultimate reality1
April 15th, 2010 at 2:20 pm
Given:
Vi = 0
dx = 100 ft
Vf = 30 mi/hr
Find:
a) t
b) a
Solution:
a) Vavg = (Vf + Vi)/2
Convert 30 mi/hr to ft/sec:
(30 mi/hr)(5280 ft/1mi)(1 hr/3600 sec)
= 44 ft/sec
Vavg = (44 ft/sec + 0)/2
Vavg = 22 ft/sec
d = Vavg(t)
100 ft = (44 ft/sec)t
t = 100 ft/44 ft/sec
t = 2.27 sec ANS
b) a = (Vf - Vi)/t
a = (44 ft/sec - 0)/2.27 sec
a = 19.4 ft/sec^2 ANS
teddy boy teddy boy