contestada

A lunar lander is making its descent to Moon base I. The lander descents slowly under the retro-thrust of its descent engine. The engine is cut off when the lander is 197 inches above the surface and has a downward speed of 0.8 m/s. With the engine off, the lander is in free fall. What is the speed of the lander just before it touches the surface? The acceleration due to gravity on the moon is 1.6 m/s 2 .

Respuesta :

xero099

Answer:

[tex]v_{f}\approx 4.081\,\frac{m}{s}[/tex]

Explanation:

The final speed of the lander is described by an uniformly accelerated motion, which is described herein:

[tex]v_{f} = \sqrt{(0.8\,\frac{m}{s} )^{2}+2\cdot (1.6\,\frac{m}{s^{2}} )\cdot (197\,in)\cdot (\frac{0.0254\,m}{1\,in} )}[/tex]

[tex]v_{f}\approx 4.081\,\frac{m}{s}[/tex]