A particle of mass š‘š is moving in the š‘„š‘¦-plane such that its velocity at a point (š‘„, š‘¦) is given as v⃗ = š›¼(š‘¦š‘„̂ + 2š‘„š‘¦̂), where š›¼ is a non-zero constant. What is the force š¹ acting on the particle? (A) š¹ = 2š‘šš›¼ 2 (š‘„š‘„̂ + š‘¦š‘¦̂ ) (B) š¹ = š‘šš›¼ 2 (š‘¦š‘„̂ + 2š‘„š‘¦̂ ) (C) š¹ = 2š‘šš›¼ 2 (š‘¦š‘„̂ + š‘„š‘¦̂ ) (D) š¹ = š‘šš›¼ 2 (š‘„š‘„̂ + 2š‘¦š‘¦̂ )

To determine the force F acting on the particle, we'll use Newton's second law, which states that the force is equal to the mass m times the acceleration a:

F=ma

First, we need to find the acceleration a. Acceleration is the time derivative of velocity v:

a=dvdt

Given the velocity vector:

v=α(yx^+2xy^)

We can express the acceleration as:

a=ddt[α(yx^+2xy^)]

Since Ī± is a constant, it can be factored out:

a=α(dydtx^+2dxdty^)

Recognize that dxdt and dydt are the components of the velocity vector v:

dxdt=αyanddydt=2αx

Substituting these into the expression for acceleration:

a=α((2αx)x^+2(αy)y^)=2α2xx^+2α2yy^

Simplifying, we get:

a=2α2(xx^+yy^)

Now, using Newton's second law to find the force:

F=ma=m2α2(xx^+yy^)=2mα2(xx^+yy^)

Thus, the correct answer is:

A

Answer: (A) F=2mα2(xx^+yy^)

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