Posted by **Tammy** on Sunday, March 25, 2007 at 1:49pm.

The position of a toy locomotive mobing on a straight track along the x-axis is given the equation x=t^3-6t^2 +9t where x is in metters and t is in seconds. The net force on the locomotive is equal to zero when t is eqaul to

a) zero

b)2 s

c)3 s

d)4s

e)5s

Would the answer be b)2 s? I found the double derivative of the equation and set x to 0 and solved for t.

f'= 3t^2 - 12t + 9

f"=6t - 12

yes, t=2

## Answer this Question

## Related Questions

- physics - The position of a toy locomotive moving on a straight track along the ...
- Physics - The position of a toy locomotive moving on a straight track along the ...
- physics - The position of a toy locomotive moving on a straight track along the ...
- physics - A girl pulls a toy train with a horizontal force of 10N The tention ...
- Physics - A particle moves along the x axis. Its position is given by the ...
- Physics - A 2.9 kg body is at rest on a frictionless horizontal air track when a...
- physics - One component of a magnetic field has a magnitude of 0.046 T and ...
- Physics - Two toy locomotives approach each other along the same line, and upon ...
- physics - A locomotive pulls a series of wagons. Which is the correct analysis ...
- Physics - One component of a magnetic field has a magnitude of 0.080 T and ...