When an object is falling and reaches a constant velocity, the net force on the object is <em>zero</em> (it's not accelerating), and the weight of the object is equal to <em>the force of air resistance against the object</em>. (choice-D)
Cause surface currents to move in circular paths.
Answer:
x = 1.00486 m
Explanation:
The complete question is:
" The potential energy between two atoms in a particular molecule has the form U(x) =(2.6)/x^8 −(5.1)/x^4 where the units of x are length and the num- bers 2.6 and 5.1 have appropriate units so that U(x) has units of energy. What is the equilibrium separation of the atoms (that is the distance at which the force between the atoms is zero)? "
Solution:
- The correlation between force F and energy U is given as:
F = - dU / dx
F = - d[(2.6)/x^8 −(5.1)/x^4] / dx
F = 20.8 / x^9 - 20.4 / x^5
- The equilibrium separation distance between atoms is given when Force F is zero:
0 = 20.8 / x^9 - 20.4 / x^5
0 = 20.8 - 20.4*x^4
x^4 = 20.8/20.4
x = ( 20.8/20.4 )^0.25
x = 1.00486 m
Answer:
1.77 x 10^-8 C
Explanation:
Let the surface charge density of each of the plate is σ.
A = 4 x 4 = 16 cm^2 = 16 x 10^-4 m^2
d = 2 mm
E = 2.5 x 10^6 N/C
ε0 = 8.85 × 10-12 C2/N ∙ m2
Electric filed between the plates (two oppositively charged)
E = σ / ε0
σ = ε0 x E
σ = 8.85 x 10^-12 x 2.5 x 10^6 = 22.125 x 10^-6 C/m^2
The surface charge density of each plate is ± σ / 2
So, the surface charge density on each = ± 22.125 x 10^-6 / 2
= ± 11.0625 x 10^-6 C/m^2
Charge on each plate = Surface charge density on each plate x area of each plate
Charge on each plate = ± 11.0625 x 10^-6 x 16 x 10^-4 = ± 1.77 x 10^-8 C
The disposition of the toxic waste materials is the greatest problem
in the field of nuclear-generated electric power today.
Nuclear-generated electric power generates NO air pollution, and
we have the mature technology to use it widely.