<span>At an instant when the displacement is equal to a/2,
Potential energy U = 1/2ka(square) where a is displacement.
when a= a/2
U = 1/4ka(square)
U = E/4
Potential Energy = 1/4 Total energy</span>
Using
F= mv²/r
4 = 0.5×v² / 2
8 /0.5 = v²
v²=16
v= √16
v= 4 ms-¹
F=mg=Gm1m2/r^2
g=Gm2/r^2
g=2Gm2/(2r)^2=2Gm2/4r^2=Gm2/2r^2
So since there is half times the gravity on this unknown planet that has twice earth's mass and twice it's radius, then the person can jump twice as high. 1.5*2= 3m high
