Please help me easy question just get mixed up.

The mechanical energy of the ball is 112.667 J

Explanation:

Mechanical energy = kinetic energy + potential energy

Where:

kinetic energy = m

potential energy = mgh

So that for the given ball, its mechanical energy = m + mgh

                                = m( + gh)

But, m = 400 g = 0.4 kg, v = 23.0 m/s, g = 9.81 m/ and h = 1.75 m.

Mechanical energy of the ball = 0.4(() + 1.75*9.81)

                                                  = 0.4(264.5 + 17.1675)

                                                  = 0.4 x 281.6675

                                                  = 112.667

The mechanical energy of the ball is 112.667 J.

the duration of a photographic flash is related to an rc time constant, which is 0.100 μs for a certain camera.