Let there be an object having some chemicals in it. It starts moving with a uniform velocity v, and a chemical reaction starts happening. In this case, which of the following statement/s is/are correct? 1) Chemical reactions happening in the system cannot

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Q: (NDA-II/2019)
Let there be an object having some chemicals in it. It starts moving with a uniform velocity v, and a chemical reaction starts happening. In this case, which of the following statement/s is/are correct? 1) Chemical reactions happening in the system cannot change the velocity v of the centre of mass of the object. 2) Chemical reactions happening in the system cannot change the kinetic energy of the particles inside with respect to the centre of mass an object weighs 36g in air and has a volume of 8.0 cmof an object.
Select the correct answer using the code given below:

question_subject: 

Science

question_exam: 

NDA-II

stats: 

0,1,8,2,1,5,1

keywords: 

{'kinetic energy': [0, 0, 4, 7], 'chemical reactions': [0, 0, 0, 1], 'chemical reaction': [0, 0, 2, 0], 'particles': [1, 0, 5, 16], 'mass': [0, 0, 2, 3], 'object': [1, 0, 11, 43], 'chemicals': [0, 0, 1, 1], 'system': [8, 3, 7, 23], 'volume': [0, 0, 1, 0]}

The correct answer is option 2 - "2 only". This means that the statement "Chemical reactions happening in the system cannot change the kinetic energy of the particles inside with respect to the centre of mass" is correct.

Let`s dissect each option to understand why option 2 is the correct answer:

Option 1 states that "Chemical reactions happening in the system cannot change the velocity v of the centre of mass of the object". This statement is incorrect. Chemical reactions can indeed change the velocity of the center of mass of an object. For example, if there is a reaction that releases gases in one direction, it can cause the object to move in the opposite direction, thus changing its velocity.

Option 2 states that "Chemical reactions happening in the system cannot change the kinetic energy of the particles inside with respect to the centre of mass." This statement is correct. The kinetic energy of the particles inside an object is determined by their mass and velocity. Chemical reactions can change the internal energy of the particles, but they do not affect the velocity or mass, so the kinetic energy remains unchanged.

Since option 1 is incorrect and option 2 is correct, the correct answer is option 2 - "2 only".

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