Answer:
1331.84 m/s
Explanation:
t = Time taken
u = Initial velocity
v = Final velocity = 0
s = Displacement = 490 km
a = Acceleration
g = Acceleration due to gravity = 1.81 m/s² = a
From equation of linear motion
[tex]v^2-u^2=2as\\\Rightarrow -u^2=2as-v^2\\\Rightarrow u=\sqrt{v^2-2as}\\\Rightarrow u=\sqrt{0^2-2\times -1.81\times 490000}\\\Rightarrow u=1331.84\ m/s[/tex]
The speed of the material must be 1331.84 m/s in order to reach the height of 490 km
Answer:
1.33 km/s
Explanation:
acceleration due to gravity, g = 1.81 m/s²
height, h = 490 km = 490000 m
Let u is the initial speed and the final speed is zero.
use third equation of motion
v² = u² - 2 g h
0 = u² - 2 x 1.81 x 490000
u² = 1773800
u = 1331.84 m/s
u = 1.33 km/s
Thus, the initial speed of the material is 1.33 km/s.
