A 50,000kg train is rolling on its own down the track at 5 m/s. You grab the rope trailing behind it, and exert a stopping force of 2000N. How long
does it take to stop the train? *

The consumption of fossil fuels could be

An object moves from the position +34m to the position -15m in 15 seconds. what is it's total displacement? what is it's average velocity?

The force acting on a beam was measured under the same operating conditions and a sample of 5 data points was collected. this process was repeated by 3 observers. the pooled standard deviations of these 3 data sets was 1.21. determine the true mean force using all pooled data (with a 95% probability). the result should look like this: true mean = mean +/- margin of error