Answer:
t = 40 s
Explanation:
Depending the current speed, assuming it is 0 m/s you have:
[tex]v_{f}=v_{i}+at \\\\v_{f} = final\ speed \\v_{i} = initial\ speed \\a = acceleration \\t = time[/tex]
1.2 km/s = 1200 m/s
[tex]1200 = 0 + 30t \\\frac{1200}{30} = t \\t = 40 s[/tex]
Answer: the rocket takes 40 seconds to reach 1200 m/s
Explanation: use the cinematic equations for velocity
(vf = vi + at)
[tex]1200\frac{m}{s} = 0\frac{m}{s}+30\frac{m}{s^{2} } *t[/tex]
[tex]t=\frac{12000\frac{m}{s} }{30\frac{m}{s^{2} } }[/tex]
t= 40 seconds
