Correct Option
The correct option is (b).
Explanation
The Newton's Laws of Motion, specifically analyzing the relationship between applied force, friction, and the resulting state of motion (acceleration vs. uniform velocity).
Statement-wise Analysis
- Statement 1 is Incorrect. According to Newton's First Law of Motion (Law of Inertia), an object in motion will continue moving at the same speed unless acted upon by an external unbalanced force. When pedalling stops, the bicycle slows down not merely because the pedalling force is absent, but because of the presence of retarding forces such as friction (between the tyres and the road) and air resistance. If these opposing forces were absent, the bicycle would continue moving perpetually even without pedalling.
- Statement 2 is Correct. To move an object at a uniform velocity, the net force acting on it must be zero (since acceleration is zero). This requires the applied force (pedalling) to exactly balance the opposing frictional force. In this state of equilibrium, the forces cancel each other out, maintaining constant speed.
- Statement 3 is Incorrect. If the pushing force is greater than the frictional force, there is a net unbalanced force acting in the direction of motion. According to Newton's Second Law ($F = ma$), a net force produces acceleration. Consequently, the velocity of the object would increase, and it would not move with a uniform velocity.
Key Takeaway: Uniform velocity implies zero acceleration, which occurs only when the net force on an object is zero. This happens when the driving force is exactly equal and opposite to the resistive forces (friction).