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webslinger67
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I am currently doing the self-test in Ch1 of Basic Physics: A Self-Teaching guide, by Karl F. Kuhn. I am trying to teach myself the basics of physics so I can be ready for March's session of physics class. I had a go at it for 2 days and realized i was going to fail unless I did something to be more comfortable with it.
ok Question 3 says:
3) an object traveling with the speed of 2 m/s. Three seconds later its speed is 14 m/s. How much is its acceleration during this time. Answer= 4 m/s
I get this by using the acceleration equation of a = (V1-V0)/t or (14-2)/3= 4 m/s
now my issue is question 5 which says:
5)How far does the object in question 3 travel during the 3 seconds of its accelerated motion?
so I worked it like this using the acceleration, distance traveled and time of fall relation equation.
d = V0(t)+1/2 * at^2 or 2(1) +1/2(4.67)(3)^2 = 23.02 m
for the V0(t) i used 2m/s times the assumed time of speed after 1 second
for the a (or acceleration) i averaged over 3 seconds the total speed of 14 m/s or 4.67 m/s
the obviously, following the equation, multiplied by the the total time of 3s squared
the book is trying to tell me 24 m is the answer, can someone tell me what I did wrong here, or is the book incorrect?
ok Question 3 says:
3) an object traveling with the speed of 2 m/s. Three seconds later its speed is 14 m/s. How much is its acceleration during this time. Answer= 4 m/s
I get this by using the acceleration equation of a = (V1-V0)/t or (14-2)/3= 4 m/s
now my issue is question 5 which says:
5)How far does the object in question 3 travel during the 3 seconds of its accelerated motion?
so I worked it like this using the acceleration, distance traveled and time of fall relation equation.
d = V0(t)+1/2 * at^2 or 2(1) +1/2(4.67)(3)^2 = 23.02 m
for the V0(t) i used 2m/s times the assumed time of speed after 1 second
for the a (or acceleration) i averaged over 3 seconds the total speed of 14 m/s or 4.67 m/s
the obviously, following the equation, multiplied by the the total time of 3s squared
the book is trying to tell me 24 m is the answer, can someone tell me what I did wrong here, or is the book incorrect?