An object is moving with a constant velocity. Is there a net force acting upon it? Class 9

An object is moving with a constant velocity. Is there a net force acting upon it? Class 9

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Question 1.

An object is moving with a constant velocity. Is there a net force acting upon it? Class 9

Answer:

No. According to Newton's first law of motion, if an object is moving with a constant velocity, the net force acting on it is zero. Constant velocity means no change in speed or direction, which means acceleration is zero. By F = ma, zero acceleration means zero net force.

Question 2.

Suppose, no net force is acting on an object. Which of the following situations are possible? Class 9

(i) Object remains at rest if at rest.

(ii) Object keeps moving with a constant velocity if already moving.

(iii) Object is moving with a constant acceleration.

Answer:

(i) Possible. If the object is at rest and no net force acts on it, it will remain at rest (Newton's first law).

(ii) Possible. If the object is already moving and no net force acts on it, it will continue to move with the same constant velocity (Newton's first law).

(iii) Not possible. A constant acceleration requires a net force (F = ma). If the net force is zero, acceleration must also be zero.