# English system

## 1003 Return in 10 seconds | Rectilinear Translation

## 1002 Location of warning torpedo | Rectilinear Translation

**Problem 1002**

On a certain stretch of track, trains run at 60 mph (96.56 kph). How far back of a stopped train should be a warning torpedo be placed to signal an oncoming train? Assume that the brakes are applied at once and retard the train at the uniform rate of 2 ft/sec^{2} (0.61 m/s^{2}).

## The US Customary System of Measures

The following are the English System of measurement

**Length**

12 inches = 1 foot

3 feet = 1 yard

220 yards = 1 furlong

8 furlongs = 1 mile

5 280 feet = 1 mile

1 760 yards = 1 mile

**Area**

144 square inches = 1 square foot

9 square feet = 1 square yard

4 840 square yards = 1 acre

640 acres = 1 square mile

1 square mile = 1 section

36 sections = 1 township