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A rocket moves upward, starting from rest with an acceleration of +30.0 m/s2 for 5.00 s. It runs out of fuel at the end of this 5.00 s and continues to move upward. How high does it rise? m

Respuesta :

Answer:

The distance covered by the rocket after fuel ran out is [tex]3442.04 m[/tex]

Explanation:

Given that the rocket moves with an acceleration [tex]a=30m/s^2[/tex]

time [tex]t=5 s[/tex]

Since the rocket starts from rest initial velocity  [tex]u=0 s[/tex]

The distance it travelled within this time is given by  [tex]s=ut+ \frac{1}{2} at^2[/tex]                                                                                                  [tex]=0 \times 5+ \frac{1}{2} (30\times25)=375 m[/tex]

Velocity at this point is given by [tex]v=u+at[/tex]

[tex]v=0+30\times5=150m/s[/tex]

Given that at this height it runs out of fuel but travels further. Here final velocity [tex]v=0[/tex](maximum height), initial velocity[tex]u=150 m/s[/tex]  and time to zero velocity [tex]t=\frac{v}{g} = \frac{150}{9.8} =15.3 s.[/tex]

Thus it travels [tex]15.3 seconds[/tex] more after fuel running out. The distance covered during this period is given

[tex]s= ut+\frac{1}{2} gt^2=150 \times 15.3+1/2 \times9.8 \times 15.3^2=3442.04 m[/tex]