Determine the mechanical energy of this object a 1 kg ball sits on a 10 m highcliff

Mechanical energy is the sum of both potential and kinetic energy. Thus, we must find both the potential and kinetic energy first.

The equation for gravitational potential energy is PE=MGH, or potential energy=Mass*gravitational acceleration*height. Since initial potential energy is equal to final kinetic energy, we can also equal our potential energy equation to the kinetic energy equation, or Kinetic Energy=1/2mass*velocity^2.

MGHinitial=1/2mv^2final.

Now, insert the values that we know. First, lets insert the mass.

(1)GHinitial=1/2(1)v^2final.

Now substitute gravitational acceleration and height into the potential energy equation.

1(9.8)(10)=1/2(1)V^2

98=1/2(1)v^2

Since KE is equal to PE, we know that both KE and PE are 98. So to solve for mechanical energy, multiply 98 by 2.

98*2=196.

The mechanical energy is 196.

Hope this helps!

1. for the first question, we must find the mass of the anhydrous salt, mgso₄. the molar mass for mgso₄·7h₂o is 246.47 g/mol, while that of mgso₄ is 120.37 g/mol.7.834 g mgso₄·7h₂o * 1 mol mgso₄·7h₂o/246.47 g * 1 mol mgso₄/1 mol mgso₄·7h₂o * 20.37 g mgso₄/mol = 0.647 g mgso₄

2. mass of water = mass of sample - mass of anhydrous salemass of water = 7.834 - 0.647 = 7.19 gpercent water in hydrate = 7.19/7.834 * 100 = 91.74%