Answer: the external agent must do work equal to -1.3 × 10⁻⁸ J
Explanation:
Given that;
Mass M1 = 7.0 kg
r = 3.0/2 m = 1.5 m
Mass M2 = 21 kg
we know that G = 6.67 × 10⁻¹¹ N.m²/kg²
work done by an external agent W = -2GM2M1 / r
so we substitute
W = (-2 × 6.67 × 10⁻¹¹ × 21 × 7) / 1.5
W = -1.96098 × 10⁻⁸ / 1.5
W = -1.3 × 10⁻⁸ J
Therefore the external agent must do work equal to -1.3 × 10⁻⁸ J
Answer:
a. 
, 
b. 
Explanation:
To calculate the values in the question, a deep understanding of perfect inelastic collision is important.
When two bodies undergo inelastic collision, two important parameters must be well understood i.e
Momentum: the momentum is always conserved in perfectly inelastic collision. i.e the total momentum after collision is the sum of the individual momentum before collision
Kinetic energy: Kinetic energy is not conserved due to dissipative force.
a.To calculate the velocity, we first find the total momentum before collision
Momentum of player 1 
Momentum of player 2 
Hence the total momentum 
Note, since the direction of movement before collision is due south and due north respectively we have to represent the velocity using the rectangular coordinate
Hence 
solving for the resultant velocity, we have
To calculate the direction of movement, we have
b. to calculate the decrease in total kinetic energy, before collision, the total kinetic was
And the final kinetic energy after collision is
The decrease in Kinetic energy is
The negative sign indicate a decrease in Kinetic energy
Answer: All apply
The periodic table is an arrangement of the chemical elements in the form of a table, ordered by:
-Their atomic number (number of protons)
-Their configuration of electrons
-Their chemical properties
It was progressively developed over time as the scientific knowledge advanced; for this reason many modifications and corrections might be done in the future.
Its usefulness lies in the fact that it allows the existing elements to be organized in a more structured and coherent way, according to the chemical properties they possess. Dividing the table into rows and columns, which represent the periods and groups or families.
Then, with the location and classification of an element according to its group, we can determine how it acts by knowing its chemical and physical characteristics.
This is how with this configuration can be distinguished 4 sets of chemical elements, according to the ease of their atoms to lose or gain electrons, transforming into ions: metals, semimetals, non-metals and noble gases.
This has helped to predict the existence of various elements that have not yet been discovered, because by elements already located in the table and the periodicity found, <u>there are still empty spaces that indicate the composition of the element that has not yet been found</u>.
In addition, this table helps to simplify in some way the teaching of chemical elements and facilitates their learning, as well as their usage in the development of technological innovations.
Answer: The correct answer is B
Explanation: The string is pulling right and the string is unraveling causing it to accelerate left
According to Newton's second law of motion, Force is the product of mass and acceleration of the object.
So, F = m * a
Here, m = 210 Kg
a = 2.4 * 10⁵ m/s²
Substitute their values,
F = 210 * 2.4 * 10⁵ N
F = 504 * 10⁵ N
F = 5.04 * 10⁷ N
In short, Your Answer would be Option B
Hope this helps!
