A body constrained to move along the \(\mathrm{z}\)-axis of a coordinate system is subjected to constant force given by \(\vec{F}=-\hat{i}+2 \hat{j}+3 \hat{k}\) where \(\hat{i},\hat{j} \) and \(\hat{k}\) are unit vectors along the \(\mathrm{x}\)-axis, \(\mathrm{y}\)-axis and \(\mathrm{z}\)-axis of the system respectively. The work done by this force in moving the body a distance of \(4\) m along the \(\mathrm{z}\)-axis will be:
1. \(15\) J
2. \(14\) J
3. \(13\) J
4. \(12\) J

Subtopic:  Concept of Work |
 89%
From NCERT
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NEET 2023 - Target Batch - Aryan Raj Singh
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To view explanation, please take trial in the course.
NEET 2023 - Target Batch - Aryan Raj Singh

A body of mass 2 kg initially at rest moves under the action of an applied horizontal force of 7 N on a table with a coefficient of kinetic friction = 0.1. The work done by the applied force in 10 s is:

1. 882 J
2. 635 J
3. 247 J
4. 120 J

Subtopic:  Concept of Work |
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NEET 2023 - Target Batch - Aryan Raj Singh
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Which one of the following statement is wrong?

1. When a conservative force does positive work on a body, the potential energy of the body decreases.
2. Work done by a body against friction always results in a loss of its kinetic energy.
3. The rate of change of the total momentum of a many-particle system is proportional to the sum of the internal forces on the system.
4. In an inelastic collision of two bodies, the total linear momentum of the system of two bodies does not change after the collision.

Subtopic:  Concept of Work | Work Energy Theorem |
 55%
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NEET 2023 - Target Batch - Aryan Raj Singh
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An electron and a proton are detected in a cosmic ray experiment, the first with kinetic energy 10 keV, and the second with 100 keV. The ratio of their speeds is:

(me9.31×10-31 kgmp1.67×10-27 kg, 1 eV = 1.60×10-19 kg).

1. 13.5: 1
2. 1: 1
3. 1: 13.5
4. 2: 1

Subtopic:  Concept of Work |
 64%
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NEET 2023 - Target Batch - Aryan Raj Singh
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