A projective of 2kg was velocities 3mls and 4mls at two points during its flight in the uniform gravitational field of the earth. If these two velocities are `bot` to each other then the minimum KE of the particle during its flight is

Explanation

`V_(1)cos alpha =V_(2)cos(90-alpha)`
`3cos alpha=4 sin alpha`
`tan alpha =3/4`
`KE_("man") =1/2mv_(1)^(2) cos^(2)alpha`
`1/2 xx 2 xx 3 xx (4/5)^(2) =(9 xx 16)/25 = 5.76` J