The electric field at (x,y,z) its equal to the negative of the gradient if the electric potential.
We have
V(x, y, z) = 2x² - 3y² + 5z
so
E(x, y, z) = -grad(V) = -(dV/dx i + dV/dy j + dV/dz k)
where d/d(variable) is meant to be a partial derivative with respect to that variable. The partial derivatives are
dV/dx = 4x
dV/dy = -6y
dV/dz = 5
and so the electric field at any point is
E(x, y, z) = -4x i + 6y j - 5k
and at (3, 4, 5) it is
E(3, 4, 5) = -12i + 24j - 5k
Using the formula:
w = m x g ....... eq1
here w is weight of the object.
m is mass of the object, and
g is the acceleration of gravity.
mass, m = 14 lbm (given)
acceleration of gravity, g= 32.0 ft/
Now, substituting the values in equation (1):
w = 14lbm x 32.0 ft/
= 448 lbm ft/
since, 1 lbf = 32.174 lbm ft/
so, w = 448 x 
w = 13.924lbf
Hence, the mass of an object is 13.924 lbf.
To know more about such questions, visit:
brainly.com/question/10936674
#SPJ4
Stencils, ruler, penciles thing like that.