Magnetometers<span> are widely used for measuring the Earth's magnetic field and in geophysical surveys to detect magnetic anomalies of various types. </span>They<span> are also used in the military to detect submarines.</span>
It takes 2 years of graduate study in a subfeild, practicum experience, and a thesis.
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Answer:
Option A is the correct answer.
Explanation:
Here momentum is conserved.
That is 
Substituting values

Speed of block A after collision = 10 m/s
Option A is the correct answer.
By looking at the acceleration of the object.
In fact, Netwon's second law states that the resultant of the forces acting on an object is equal to the product between the mass m of the object and its acceleration:

So, when static friction is acting on the object, if the object is still not moving we know that all the forces are balanced: in fact, since the object is stationary, its acceleration is zero, and so the resultant of the forces (left term in the formula) must be zero as well (i.e. the forces are balanced).
False because the physics is like a science and it’s like a math