Friday

November 28, 2014

November 28, 2014

Posted by **George** on Wednesday, November 12, 2008 at 5:02pm.

traveled another mile, it is going 80 mph, and the plane has traveled another 5 miles and is going 500 mph. At that moment, how fast is the distance between the train and the plane increasing?

Is the answer 105 mph.

- Calculus -
**drwls**, Wednesday, November 12, 2008 at 5:26pmMeasuring time (t) in hours from that moment, the vector distance R between train and plane at later times is

R = (1+80t) i + (5+ 500t) j + 4 k

where i, j and k are unit vectors west, north and vertical.

dR/dt = 80 i + 500 j

The magnitude of that rate of change is

sqrt[(80)^2 + (500)^2] = 506 mph.

This could also have been solved simply by taking the magnitude of the relative velocity vector, 80 i + 500 j mph

**Answer this Question**

**Related Questions**

Calculus - A train is heading due west from St. Louis. At noon, a plane flying ...

calculus - 26. A train is heading due west from St. Louis. At noon, a plane ...

college - A train is heading due west from St. Louis. At noon, a plane flying ...

Math Calculus 2 - At a certain instant an aircraft flying due east at 240 miles ...

Math - a plane flies due north at 300 mi/h for 3 h then due west at 250 mi/h. If...

calculus - a plane flying horizontally at an altitude of 2 mi and a speed of 460...

Algerbra - Can anyone help me on these two problems also. I am getting so ...

Physics - A train moving with constant velocity travels 190 north in 14s and an ...

physics - You are on an airplane traveling 30° south of due west at 130.0 m/s ...

calculus - An airplane flying west at 300 miles per hour goes over the control ...