Answer:
114.44 J
Explanation:
From Hook's Law,
F = ke................. Equation 1
Where F = Force required to stretch the spring, k = spring constant, e = extension.
make k the subject of the equation
k = F/e.............. Equation 2
Given: F = 10 lb = (10×4.45) N = 44.5 N, e = 4 in = (4×0.254) = 1.016 m.
Substitute into equation 2
k = 44.5/1.016
k = 43.799 N/m
Work done in stretching the 9 in beyond its natural length
W = 1/2ke²................. Equation 3
Given: e = 9 in = (9×0.254) = 2.286 m, k = 43.799 N/m
Substitute into equation 3
W = 1/2×43.799×2.286²
W = 114.44 J
Answer:
<em>D. The total force on the particle with charge q is perpendicular to the bottom of the triangle.</em>
Explanation:
The image is shown below.
The force on the particle with charge q due to each charge Q = 
we designate this force as N
Since the charges form an equilateral triangle, then, the forces due to each particle with charge Q on the particle with charge q act at an angle of 60° below the horizontal x-axis.
Resolving the forces on the particle, we have
for the x-component
= N cosine 60° + (-N cosine 60°) = 0
for the y-component
= -f sine 60° + (-f sine 60) = -2N sine 60° = -2N(0.866) = -1.732N
The above indicates that there is no resultant force in the x-axis, since it is equal to zero (
= 0).
The total force is seen to act only in the y-axis, since it only has a y-component equivalent to 1.732 times the force due to each of the Q particles on q.
<em>The total force on the particle with charge q is therefore perpendicular to the bottom of the triangle.</em>
An element which is highly conductive, highly reactive, soft, and lustrous is most likely an alkali metal.
Alkali metals are in group 1 of the Periodic table which means that they have only a single valence electron.
This causes them to be soft and highly reactive because:
- The single valance electron leads to weak bonds amongst the element's atoms which makes them soft
- The elements want to lose the single valance electron so as to become stable so they will react with other elements to give away the electron.
Examples of alkali electrons include:
- Lithium
- Sodium
- Potassium etc
In conclusion therefore, alkali metals are highly reactive and soft and so the element described above is most likely an alkali metal.
<em>Find out more at brainly.com/question/18722874.</em>
Answer:
Oligopoly
Explanation:
An oligopoly is the structure of the market that is characterized by the domination of a few firms or industries. Other small firms also operate in the same market, but the power concentration is associated with few firms only. Interdependency among the firms helps in planning and strategy making to introduce new ideas to increase the market activities. The competition in the market is reduced when a few of the firms dominate the market. It results in an increase in the price of commodities.