A body is at rest on the surface of the earth. Which one among the following statements is correct regarding this?

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Q: 97 (NDA-II/2010)
A body is at rest on the surface of the earth.
Which one among the following statements is correct regarding this?

question_subject: 

Science

question_exam: 

NDA-II

stats: 

0,15,9,2,6,15,1

keywords: 

{'net upward force': [0, 0, 1, 0], 'net downward force': [0, 0, 1, 0], 'body': [27, 3, 23, 37], 'force': [0, 0, 0, 2], 'surface': [1, 0, 0, 0], 'earth': [0, 1, 1, 1], 'rest': [0, 1, 2, 5], 'weight': [0, 0, 1, 1]}

Option 1 states that no force is acting on the body. This is incorrect because the body is experiencing the force of gravity exerted by the Earth.

Option 2 states that only the weight of the body acts on it. This is partially correct because the weight of the body is the force of gravity pulling it downwards. However, there are other forces acting on the body, such as normal force and possibly friction.

Option 3 states that the net downward force is equal to the net upward force. This is the correct statement. When an object is at rest on the surface of the Earth, the net force acting on it is zero. This means that the force of gravity pulling the object downwards is balanced by an equal and opposite upward force, known as the normal force. The normal force is exerted by the surface that the object is resting on and prevents it from sinking into the ground.

Option 4 states that none of the above options are correct. This is incorrect because option 3 is the correct statement.