Monday
September 15, 2014

Homework Help: calculus

Posted by Daniel on Sunday, March 4, 2012 at 9:06pm.

A plane flying horizontally at an altitude of 1 mi and a speed of 500 mi/h passes directly over a radar station. Find the rate at which the distance from the plane to the station is increasing when it is 2 mi away from the station.

I drew a diagram and figured out I need to find dd/dt which is the distance of the plane from the radar station over time

I found y to be the altitude of the plane (1 mi)

I also found x to be the distance away from the radar station (2 mi)

dc/dt = 500 mi/h

I noticed I could use the pythagorean equation here.

d^2 = x^2 + y^2

I solved for d to be sqrt(5)

and I differentiated the equation to be 2d*(dd/dt) = 2x*(dx/dt) + 2y*(dy/dt)

y is constant therefore dy/dt = 0

I evaluated it to be (dd/dt) = [2(2)(500)]/(2sqrt(5)) or 1000/sqrt(5)
which is equivalent to 447mi/hr



My problem is the answer is 250sqrt(3) which is 433mi/hr

What am I doing wrong?

Answer this Question

First Name:
School Subject:
Answer:

Related Questions

CALCULUS - A plane, flying horizontally at an altitude of 1 km and a speed of ...
calculus - a plane flying horizontally at an altitude of 2 mi and a speed of 460...
calculus - A plane flying horizontally at an altitude of 1 mi and a speed of 560...
Cal - A plane flying horizontally at an altitude of 3 mi and a speed of 480 mi/h...
Calc - A plane flying horizontally at an altitude of 1 mi and a speed of 510 mi/...
math cal - A plane flying horizontally at an altitude of 3 mi and a speed of 480...
Calc - How do I do this related rates problem? A plane flying horizontally at an...
calculus - A plane that is flying horizontally at an altitude of 6 kilometers ...
Calc - A plane that is flying horizontally at an altitude of 6 kilometers and a ...
Calculus - A plane flying with a constant speed of 4 km/min passes over a ground...

Search
Members