Processing Math: Done
To print higher-resolution math symbols, click the
Hi-Res Fonts for Printing button on the jsMath control panel.

No jsMath TeX fonts found -- using image fonts instead.
These may be slow and might not print well.
Use the jsMath control panel to get additional information.
jsMath Control PanelHide this Message


jsMath

Solution 8.5b

From Mechanics

Jump to: navigation, search

From part a) we have

v=(80+t )i+4t j.

and

r=(80t+21t 2 )i+2t 2 j


We see the height is

Thus the time when the aeroplane is at a height 50 m.

We see the height is 2t 2 for any time t.

Thus the time when the aeroplane is at a height 50 m is given by

2t 2=50

or

t=5 s

At this time the velocity is

v=(80+5)i+45 j=85i+20j

The speed is the magnitude of this velocity


852+202=87.3 ms1