A person throws an object on a horizontal frictionless plane surface. It is noticed that there are two forces acting on this object(i) gravitational pull and (ii) normal reaction of the surface. According to the third law of motion, the net resultant forc

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Q: 59 (CDS-II/2017)
A person throws an object on a horizontal frictionless plane surface. It is noticed that there are two forces acting on this object—(i) gravitational pull and (ii) normal reaction of the surface. According to the third law of motion, the net resultant force is zero.
Which one of the following can be said for the motion of the object?

question_subject: 

Science

question_exam: 

CDS-II

stats: 

0,14,32,11,12,9,14

keywords: 

{'net resultant force': [0, 0, 1, 1], 'forces': [0, 0, 0, 1], 'horizontal frictionless plane surface': [0, 0, 0, 1], 'acceleration': [0, 0, 2, 8], 'motion': [0, 0, 0, 3], 'deceleration': [0, 0, 1, 1], 'gravitational pull': [0, 0, 2, 1], 'normal reaction': [0, 0, 0, 2], 'constant velocity': [0, 0, 0, 2], 'third law': [0, 0, 0, 1], 'surface': [1, 0, 0, 0], 'object': [1, 0, 11, 43], 'constant speed': [0, 0, 2, 5], 'direction': [0, 0, 0, 3]}

The correct answer to this question is option 4: The object will move with constant velocity.

In this scenario, the object is on a horizontal frictionless plane surface, which means that there is no force opposing its motion. The two forces acting on the object are the gravitational pull and the normal reaction of the surface.

According to Newton`s third law of motion, for every action, there is an equal and opposite reaction. In this case, the force of gravity pulling the object downwards is balanced by the normal reaction of the surface pushing the object upwards. These two forces cancel each other out, resulting in a net force of zero.

When the net force on an object is zero, it means that the object will either remain at rest or move with a constant velocity. In this case, since the object was thrown, it will continue to move, but its velocity will not change. It will move in a straight line with constant speed and direction.

Therefore, the correct statement for the motion of the object is that it will move with constant velocity.

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