a body is projected vertically upwards with a speed of 4 km/s.how high will it rise neglect air resistance .(radius earth =6400km, g=9.8 m/s²)

Dear Student

Highest point at which body reaches can be calculated by using third equation of motion and considering that at highest point final speed v = 0.

$$\begin{gathered} v^2 =u^2-2ah \\ 0 ={\left(4000 m/s\right)}^2 -2\left(9.8 m/s^2\right)h \\ h=816326 m = 816.32 km \end{gathered}$$
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