What is the formula for calculating the momentum of an object? (p = momentum, m = mass, a = acceleration, v = velocity)
Show answer & explanation
Correct answer: C
Explanation
The correct answer is Option 3: p = mv
Explanation:
In physics, the momentum of an object is defined as the product of its mass and velocity.
• Definition: Momentum represents the 'quantity of motion' of a moving object.
• Mathematical Formula: p = m × v
o Where p = Momentum
o m = Mass
o v = Velocity
Key Characteristics of Momentum:
1. Vector Quantity: Momentum possesses a specific direction, which is the same as the direction of the object's velocity.
2. SI Unit: The SI unit of momentum is kilogram-meter per second (kg·m/s).
3. Dependence: If an object's mass or velocity increases, its momentum will also increase. For example, a heavy truck has much greater momentum than a light car traveling at the same velocity.
Analysis of Other Options:
• p = ma (Option 2): This is the formula for Force, not momentum (F = ma). According to Newton's Second Law of Motion, force is the product of mass and acceleration.
Additional Facts:
• Newton's Second Law: The rate of change of an object's momentum is directly proportional to the force applied to it (F = Δp / Δt).
• Law of Conservation of Momentum: If no external force acts upon a system, its total momentum remains constant.
Potential Questions for Upcoming Exams:
Question: What is the SI unit of momentum?
Answer: kg·m/s
Question: If an object's velocity is doubled, what effect will this have on its momentum?
Answer: The momentum will also double.
Question: Why does a player pull their hands backward while catching a moving cricket ball?
Answer: To increase the time interval over which the momentum changes, thereby reducing the force exerted on the hands.