Question #bcf2d

1 Answer
Dec 30, 2016

sf(16.2color(white)(x)"m/s")

Explanation:

MFDocs

See fig. (a)

First we find the vertical component of the motion using:

sf(v^2=u^2+2as)

This becomes:

sf(v_y^2=0+2xxgxxh)

sf(v_y^2=0+2xx9.81xx6=117.72)

sf(v_y=sqrt(117.72)=10.85color(white)(x)"m/s")

See fig (b).

The horizontal component of velocity is constant so we can find the resultant velocity sf(V_(res)) using Pythagoras:

sf(12^2+10.85^2=V_(res)^2)

:.sf(V_(res)^2=261.72)

sf(V_(res)=sqrt(261.72)=16.2color(white)(x)"m/s")

If you were asked to find the angle to the vertical then:

sf(tantheta=12/10.85=1.105)

From which sf(theta=48^@)