Aprojectile was launched horizontally with a velocity of 468m/s, 1.86m above the ground how long did it take the projectile to hit the ground

0.616 s to 3 significant figures

Explanation:

Using the equation s=ut+0.5at^2 in the vertical direction:

1.86=0×t+0.5gt^2

1.86=4.905t^2

t^2=1.86÷4.905

t=0.6157961457

=0.616 s (3sf)

the minimum amperage that the current in this wire would have to have so that its weight is completely supported by the magnetic force due to earth's field, assuming that no other forces except gravity act on it