The height `y` nad the distance `x` along the horizontal plane of a projectile on a certain planet (with no surrounding atmosphere) are given by `y = (8t - 5t^2) m` and `x = 6t m`, where `t` is in seconds. The velocity with which the projectile is projected at `t = 0` is.A. `8 m s^-1`B. `6 m s^-1`C. `10 m s^-1`D. Not obtainable from the data.

The height `y` nad the distance `x` along the horizontal plane of a pr

1.	The height `y` nad the distance `x` along the horizontal plane of a projectile on a certain planet (with no surrounding atmosphere) are given by `y = (8t - 5t^2) m` and `x = 6t m`, where `t` is in seconds. The velocity with which the projectile is projected at `t = 0` is.A. `8 m s^-1`B. `6 m s^-1`C. `10 m s^-1`D. Not obtainable from the data.
Answer» Correct Answer - C ( c) `x = 6t, u_x = (dx)/(dt) = 6` `y = 8t - 5t^2, v_y = (dy)/(dt) = 8 - 10 t` `v_y_(t = 0) = 8 ms^-1` `u = sqrt(u_x^2 + u_y^2) =sqrt(6^2 + 8^2) = 10 ms^-1`.

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