Answer
By F = -kx {-ve just indicating the sign of the force}
=>35 = k x (85-50) x 10^-2
=>k = 100 N/m
Again by F = -kx
Answer:
C
Explanation:
Answer A: A surface wave is a wave that travels along the surface of a medium.
Answer B, C: Electromagnetic waves are waves that have no medium to travel whereas mechanical waves need a medium for its transmission.
Answer D: The sentence in the answer D does not fit to the blank in the definition ( of the question )
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Hope this answer can help you.
Let us consider two vectors A and B.
As per the question, the two vectors are perpendicular to each other.
Hence the angle between them 
We are asked to calculate the resultant of these two vectors.
As per parallelogram law of vector addition, the resultant of two vectors are-
[cos90=0]
This is the way by which we can add two perpendicular vectors.
Answer:
Explanation:
Give that,
Spring constant (k)=40N/m
Force applied =75N
Since the force is applied to the right, we don't know if it is compressing or stretching the spring
So let assume it compress
Using hooke's law
F=-ke
e=-F/k
Then, e=-75/40
e=-1.875m
The deformation is 1.875m.
Let assume it stretch
Using hooke's law
-F=-ke
e=F/k
Then, e=75/40
e=1.875m
The elongation is 1.875m
It really depends on how far or close the planet is from the sun
