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

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

  1. 👍 0
  2. 👎 0
  3. 👁 177

Respond to this Question

First Name

Your Response

Similar Questions

  1. Physics

    A spring-loaded toy gun is used to shoot a ball of mass m=1.5 kg straight up in the air. The spring has spring constant k=667 N/m. If the spring is compressed a distance of 25.0 centimeters from its equilibrium position and then

    asked by Eden on October 17, 2010
  2. Physics

    A diver can reduce her moment of inertia by a factor of about 3.5 when changing from a straight position to a tuck position. If she makes two rotations in 1.5s when in the tuck position, what is her rotational speed (rot/s) when

    asked by Bella on April 20, 2010
  3. math

    Sean has 8-inch pieces of toy train track and Ruth has 18-inches of train track. How many of each piece would each child need to build tracks that are equal in length?

    asked by Anonymous on November 30, 2014
  4. math

    A toy rocket is launched straight up into the air with an initial velocity of 60 ft/s from a table 3 ft above the ground. If acceleration due to gravity is –16 ft/s2, approximately how many seconds after the launch will the toy

    asked by mitch on June 7, 2016
  5. Science

    At a distance L equals to 400m from the traffic light, brakes are applied to a locomotive moving at a velociy VEquals to 54 km/hr. Determine the position of the locomotive relative to the traffic light l minute after application

    asked by Kapil on June 10, 2017
  1. physics

    A locomotive is pulling 17 freight cars, each of which is loaded with the same amount of weight. The mass of each freight car (with its load) is 37,000 kg. If the train is accelerating at 0.7 m/s2 on a level track, what is the

    asked by badz on August 4, 2012
  2. math

    There is a diagram of a running track. The track is made up of two straights and two semicircles. The radius of each semicircle is 35 meters. The length of the outer perimeter of the entire running track is 400 meters. Find the

    asked by Melanie on May 19, 2016
  3. physics

    A locomotive pulls a series of wagons. Which is the correct analysis of the situation? A. because action always equals the reaction,the locomotive cannot pull the wagons,-the wagons pull backward just as hard as the locomotive

    asked by alexa on July 12, 2011
  4. Physics

    The rolling resistance for steel on steel is quite low; the coefficient of rolling friction is typically μr=0.002. Suppose a 180,000 kg locomotive is rolling at 19 m/s on level rails. A) If the engineer disengages the engine, how

    asked by Elias on November 12, 2017
  5. Physics

    An engineer in a locomotive sees a car stuck on the track at a railroad crossing in front of the train. When the engineer first sees the car, the locomotive is 210 m from the crossing and its speed is 26 m/s. If the engineer’s

    asked by Jennifer on September 15, 2010
  6. Physics ang. momentum

    A diver can reduce her moment of inertia by a factor of about 3.5 when changing from the straight position to the tuck position. If she makes 2.0 rotations in 1.5s when in the tuck position, what is the percent change in her

    asked by Taylor on December 7, 2009

You can view more similar questions or ask a new question.