Take east to be the positive direction. Then the resultant force from adding <em>F</em>₁ and <em>F</em>₂ is
<em>F</em>₁ + <em>F</em>₂ = (-45 N) + 63 N = 18 N
which is positive, so it's directed east.
To this we add a third force <em>F</em>₃ such that the resultant is 12 N pointing west, making it negative, so that
18 N + <em>F</em>₃ = -12 N
<em>F</em>₃ = -30 N
So <em>F</em>₃ has a magnitude of 30 N and points west.
<h2>
Spring constant is 14.72 N/m</h2>
Explanation:
We have for a spring
Force = Spring constant x Elongation
F = kx
Here force is weight of mass
F = W = mg = 0.54 x 9.81 = 5.3 N
Elongation, x = 36 cm = 0.36 m
Substituting
F = kx
5.3 = k x 0.36
k = 14.72 N/m
Spring constant is 14.72 N/m
Answer:

Explanation:
Given: The latent heat of fusion for Aluminum is 
mass to be malted m = 0.75 Kg
Energy require to melt E = mL

Therefore, energy required to melt 0.75 Kg aluminum

Answer:
η = 40 %
Explanation:
Given that
Qa ,Heat addition= 1000 J
Qr,Heat rejection= 600 J
Work done ,W= 400 J
We know that ,efficiency of a engine given as

Now by putting the values in the above equation ,then we get

η = 0.4
The efficiency in percentage is given as
η = 0.4 x 100 %
η = 40 %
Therefore the answer will be 40%.
<span>Chronological essays by the definition of a chronological
meaning in order. There is an order in a specific writing. Like a history write
up from a certain happening years ago. It
is different from procedural essays because these are essays who are giving
instructions of certain set up to guide the person accordingly in doing
something to make it more accurate. Like recipes, instructions in playing, etc.
Example words that are used in chronological essays are first, second, third,
fourth, fifth, next, after, then, lastly, finally, consequently, in addition,
thus, therefore, however, etc.</span>