25,000 Feet = 7620m
PE = mgh where m is mass, g is gravity accel: 9.8 n h is height
= 90 x 9.8 x 7620
= 6720840J
= 6.72MJ
F = ma where m is mass, a is accel = gravity = 9.8
= 90 x 9.8
= 882N
Accel = gravity = 9.8m/s^2
KE = 1/2mv^2 where m is mass n v is vel
if no wind resistance, PE leaving airplane = KE at net
6720840 = 1/2 x 90 x v^2
v^2 = 149352
v = 386.5m/s
Kinetic energy is energy that a body possesses by virtue of being in motion, there for if an object is moving, it has kinetic energy.
Example; A roller coaster sitting on top of hill has potential energy. When it starts to move and is going down the hill, it has kinetic energy. :)
Gravitational potential energy can be given by the equation
PE = mgh
where m is the mass,
g is the gravitational constant 9.81 or 10 depending on rounding
and h is the height
well weight is a force equiavlent to
W= m*g
so comparing that to the potential energy equation, divide the potential energy by the height and you will get weight in Newtons
D.) White Dwarf
It is the smallest star whose mass is approximately equal or greater than 1.4M
Here, M = mass of the Sun.
Hope this helps!