A body is thrown vertically upwards with a velocity of 98m/s. If g=a=9.8 m/s when will it reach its highest point

it is at its highest when the velocity drops to zero and it starts to fall.

v = Vo - at = 98 - 9.8t

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To determine when the body will reach its highest point, we can use the kinematic equation for vertical motion:

v^2 = u^2 + 2as

Where:
v = final velocity (0 m/s at the highest point)
u = initial velocity (98 m/s)
a = acceleration (equal to gravitational acceleration, -9.8 m/s^2 for upward motion)
s = displacement (output desired)

Rearranging the equation, we have:

0^2 = (98)^2 + 2(-9.8)s

0 = 9604 - 19.6s

Solving for s, we get:

19.6s = 9604

s = 9604 / 19.6

s = 490.2 m

Since s represents displacement, and at the highest point, displacement is zero, we can conclude that the body will reach its highest point after traveling 490.2 meters upwards.