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QJEEM23Ph6616: JEE Main 2023 Physics - Class 11 JEEM23Ph6616 Solution: Three forces are acting on a particle of mass . The forces and…

Three forces F1=10 N,F2=8 N, F3=6 NF_{1}=10 \mathrm{~N}, F_{2}=8 \mathrm{~N}, \mathrm{~F}_{3}=6 \mathrm{~N} are acting on a particle of mass 5 kg5 \mathrm{~kg} . The forces F2\mathrm{F}_{2} and F3\mathrm{F}_{3} are applied perpendicularly so that particle remains at rest. If the force F1F_{1} is removed, then the acceleration of the particle is:

Multiple Choice Options

  • A 4.8 ms−24.8 \mathrm{~ms}^{-2}
  • B 7 ms−27 \mathrm{~ms}^{-2}
  • C 2 ms−22 \mathrm{~ms}^{-2}
  • D 0.5 ms−20.5 \mathrm{~ms}^{-2}

Step-by-Step Verified Solution

Since the particle is initially at rest, the net force acting on it is zero. This means that the forces F1F_1 , F2F_2 , and F3F_3 are balanced. Given that F2F_2 and F3F_3 are acting perpendicularly, we can represent the balance of forces as follows:

F1=F22+F32F_1 = \sqrt{F_2^2 + F_3^2}

We can now calculate the equivalent force resulting from F2F_2 and F3F_3 :

F1=(8 N)2+(6 N)2=64+36=100=10 NF_1 = \sqrt{(8 \mathrm{~N})^2 + (6 \mathrm{~N})^2} = \sqrt{64 + 36} = \sqrt{100} = 10 \mathrm{~N}

Since the particle is initially at rest, when the force F1F_1 is removed, only F2F_2 and F3F_3 remain. The net force acting on the particle is the equivalent force resulting from F2F_2 and F3F_3 , which we have calculated to be 10 N10 \mathrm{~N} .

Now, we can use Newton's second law to find the acceleration of the particle:

F=maF = ma

Where:

  • FF is the net force acting on the particle
  • mm is the mass of the particle
  • aa is the acceleration of the particle

Rearranging the equation to solve for aa :

a=Fma = \frac{F}{m}

Plugging in the values for FF and mm :

a=10 N5 kg=2 ms−2a = \frac{10 \mathrm{~N}}{5 \mathrm{~kg}} = 2 \mathrm{~ms}^{-2}

The acceleration of the particle when the force F1F_1 is removed is 2 ms−22 \mathrm{~ms}^{-2} , which corresponds to Option C.

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