Question

In the example given below, which of Newton's Laws of Motion will apply? Justify your answer: When a cricket and tennis ball are thrown with the same force, the tennis ball moves with greater acceleration.

Hint:

Mass acts as the body's natural resistance to changes in motion (inertia). More mass means less acceleration when using the same amount of force.

Answer 1

Step 1: Identifying the Applicable Law:
This scenario is governed by Newton's Second Law of Motion, also known as the Law of Acceleration.

Step 2: Defining the Physical Law:
Newton's Second Law states that the acceleration ($a$) of an object is directly proportional to the net force ($F$) acting on it and inversely proportional to its mass ($m$). This relationship is expressed by the formula: $$F = m \cdot a \quad \implies \quad a = \frac{F}{m}$$

Step 3: Providing the Biomechanical Justification:
A standard cricket ball has a significantly larger mass ($m_{\text{cricket}}$) compared to a lighter tennis ball ($m_{\text{tennis}}$). According to the equation $a = \frac{F}{m}$, when an identical force ($F$) is applied to both objects, the resulting acceleration is inversely proportional to their masses. Because the tennis ball has less mass, it experiences much higher acceleration, causing it to travel with a greater increase in speed.