Answer: -2 km
Explanation:
If we imagine Jin's movement to be the hypothenuse of a right triangle, then the southern component of Jin's movement corresponds to the side of the triangle opposite to the angle of 30 degrees. Therefore, the magnitude of this southern component is given by
However, the angle of 30 degrees is south of east: this means that the direction of this southern component is south, and since we generally take north as positive direction, we must add a negative sign, so the correct answer is
-2 km
Answer:
The correct answer is a rarefaction.
Explanation:
Sound waves are longitudinal waves that propagate in a medium, such as air. As the vibration continues, a series of successive condensations and rarefactions form and propagate from it. The pattern created in the air is something like a sinusoidal curve to represent a sound wave.
There are peaks in the sine wave at the points where the sound wave has condensations and valleys where it has rarefactions.
Have a nice day!
<em>Choice-A </em>is a true statement. The string holding the ball in orbit is a contact force, whereas gravity is a non-contact force.
Choice-C is half-true. The string keeps the distance between the bodies constant, but gravity doesn't "MAKE" the distance vary.
<h2>5.3 km</h2>
Explanation:
This question involves continuous displacement in various directions. When it becomes difficult to imagine, vector analysis becomes handy.
Let us denote each of the individual displacements by a vector. Consider the unit vectors 
as the unit vectors in the direction of East and North respectively.
By simple calculations, we can derive the unit vectors 
in the directions North, 
South of West and 
North of West respectively.
So Total displacement vector = Sum of individual displacement vectors.
Displacement vector = 
Magnitude of Displacement = 
∴ Total displacement = 
