Physical change and I think you mean soaked.
Answer:
I believe it's 8.09 seconds, but I'm rusty on my physics.
Explanation:
The equation for solving the time it takes for an object to fall is 
So multiply the distance times 2, and you get 642 meters. Then you divide by gravities acceleration constant, 9.8, and you get 65.51. Finally,
, and you get 8.09 seconds.
I pulled the equation off of wikipedia and I'm unsure if it's the correct one, so hopefully this is correct. :/
Answer:
V = 20 m/s
Explanation:
Given the following data;
Mass = 80kg
Kinetic energy = 16,000 joules
To find the velocity;
Kinetic energy can be defined as an energy possessed by an object or body due to its motion.
Mathematically, kinetic energy is given by the formula;

Where;
K.E represents kinetic energy measured in Joules.
M represents mass measured in kilograms.
V represents velocity measured in metres per seconds square.
Substituting into the formula, we have;
16000 = ½*80*V²
16000 = 40V²
V² = 16000/40
V² = 400
Taking the square root of both sides, we have;
V = 20 m/s
Answer:
See Explanation
Explanation:
According to Newton's second law of motion, the acceleration of a body is proportional to the net external force that acts on the body.
A body accelerated when it is acted upon by an unbalanced net external force.
When the external forces acting on a body are balanced, the effect of each force is cancelled by the other hence the body is not accelerated according to Newton's second law.