Given: v0= 18.0 m/s, y0=0m, yf=11m, g=-9.81 m/s^2
v0= initial velocity, vf= final velocity, y0= initial height, yf= final height, g= gravity, sqrt()= square root, ^2=squared
vf^2=v0^2 + (2)(g)(yf-y0)
vf^2=(18.0 m/s)^2+(2)(-9.81 m/s^2)(11 m-0m)
vf^2=18.0 m/s)^2 + (-19.62 m/s^2)(11 m)
vf^2=(324 m^2/s^2) - (215.82 m^2/s^2)
vf^2=108.18 m^2/s^2
vf=sqrt(108.18 m^2/s^2)
vf=10.4 m/s
False, the ice box was invented in the 1930's, the earliest for of food preservation was probably a shaded place, cave or smoking the food. the earliest forms of food preservation are hard to prove and I don't know what they are either I was just making and educated guess.
Answer:
Net external force acting on the rock when it is at the top of its trajectory is force due to gravity (mg).
Explanation:
The forces acting on a rock thrown up are force due to gravity and air resistance. Air resistance is directly proportional to velocity of rock, when velocity is zero air resistance is zero. When it is at the top of its trajectory its velocity is zero. So air resistance is also zero. Hence only gravitational force acts on the rock.
Net external force acting on the rock when it is at the top of its trajectory is force due to gravity (mg).
The first step Hydrogen fusion process a nucleus of Deuterium (2H)is formed for two protons with the emission of an antielectron and neutronic.
University of Oregon.
It will have a greater effect on an object with greater mass because G = m * g, where G is the gravitational force, m is mass and g is the acceleration of Earth.