if an object is projected upward with an initial velocity of 80 ft per second, what is t at maximum height

The time at maximum height is 2.49 s.

Explanation:

The time (t) at the maximum height can be found using the following equation:

Where:

: is the final velocity = 0 (at the maximum height)

: is the initial velocity = 80 ft/s

g: is the gravity = 9.81 m/s²

Hence, the time is:

Therefore, the time at maximum height is 2.49 s.

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two charges are fixed in place on the x-axis as shown. the charge at x = 0 is negative and has magnitude q = 2 μcoulombs (1 μcoulomb = 10-6 coulombs). the charge at x = d, (d = +12 cm), is positive and has magnitude q = 4 μcoulombs. find a point x = xo along the x-axis at which the electric field is zero.