Calculate the gravitational potential energy of the interacting pair of the Earth and a 14kg block sitting on the surface of the Earth. You would need to supply the absolute value of this result to move the block to a location very far from the Earth (actually, you would need to use even more energy than this due to the gravitational potential energy associated with the Sun-block interacting pair).

The gravitational potential energy is

8.74 ×10^8Joules

Explanation:

To find the gravitational potential energy between ANY two objects that have mass, such as the Earth and the moon, you need to know the universal gravitational constant (G), the mass of the two objects (M and m), and the center to center distance between them (r).

The equation for determining gravitational potential energy Ug = - GMm/r

Where G = gravitational constant 6.67×10^-11

r = radius of the earth = 6.378×10^6m

M = mass of the earth = 5.97 ×10^24kg

m = mass of object = 14kg

Substituting into the equation

Ug = [( 6.67×10^11)(5.97×10^24)(14)] / (6.378×10^6)

Ug = (5.575×10^15)/(6.378×10^6)

Ug = 8.74 ×10^8 Joules

U = 8.75×10⁸J

Explanation:

U = gravitational potential energy = GMm/Re

G = Gravitational constant = 6.67×10-¹¹ Nm²/kg²

M = mass of the earth = 5.98×10²⁴kg

m = mass of the block = 14kg

Re = distance of the object from the center of the object = radius of the earth = 6.38×10⁶m

U = (6.67×10-¹¹ ×5.98×10²⁴×14)/(6.38×10⁶)

U = 8.75×10⁸J

nec chapter 5 contains

c. information on special occupancy areas

nec chapter 6 covers

a. special equipment

which of the following rules contain the words shall or shall not and must be adhered to?

b. mandatory rules

which of the following rules identify actions that are allowed but not required and typically cover options or alternative methods?

c. optional rules

which of the following serves as the introduction to the nec and provides an overview of the book?

a. nec article 90

organizations that test products for safety are

c. nrtls

the nec is published by the

a national fire protection association

the nec is divided into

b. 9 chapters

the nec provides informative annexes for

c. informational materials and examples

two terms from nec article 100 that trainees should become familiar with are

b. labeled and listed

explanation:

can be answered using momentum.

momentum = p

p1= mass1 * velocity1

p1 = p2

therefore

p1 = 6kg * 4m/s

p1 = 24kgm/s

p2=m2 * v2

24 kgm/s = 7kg * v2

v2 = 24 kgm/s / 7kg

v2= 3.42 m/s