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bassplayer142
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Homework Statement
A car takes a trip at 20m/s for a certain time interval. At any point in the trip (assuming it doesn't matter), the car takes a 10 minute break with no velocity. The average velocity for the trip is 15m/s The problem asks for the Total time and the distance travelled.
Homework Equations
x=vt
v(avg)=1/2(v+v_f)
The Attempt at a Solution
I guess I'm just confused about the rules in using the average velocity equation. This problem should be easy it seems. I have worked it out and I don't have an answer on if what I did is right or not. This is what I did.
T(total)=t(interval)+600(seconds)
x=v*t
x=v*(T-600(seconds))
x=20T-12000(meters)
2*V(avg)=v_o+v_f
=(x_o+x_f)/T=2*X/T
v(avg)=x/T Which makes me think this wasnt even necessisary since it is a general eq.
Plugging in x into the last equation you get
v(avg)*T = 20T-12000(m)
15*T=20T-12000(m)
T=2400s
Therefore x = 36000m
If this is right I would be helpful to know. If not a hint on how to use that stupid average formula would be nice.