Second law

• What is the equation that describes Newton's Second Law of motion?

  $F =$$m \cdot a$
• What does the variable F represent in the equation F = ma?

  Force measured in newtons (N)
• What does the variable m represent in the equation F = ma?

  Mass measured in kilograms (kg)
• What does the variable a represent in the equation F = ma?

  Acceleration measured in metres per second squared (m/s²)
• How does the acceleration of an object relate to the resultant force acting on it?

  The acceleration is proportional to the resultant force on the object.
• How does the acceleration of an object relate to its mass?

  The acceleration is inversely proportional to the mass of the object.
• What is inertial mass?

  A measure of how difficult it is to change the velocity of an object.
• How is inertial mass defined mathematically?

  As the ratio of force over acceleration.
• Calculate the force needed to accelerate a 22 kg cheetah at 15 m/s².


  $F =$$22 \times 15 =$$330~N$
• Calculate the force needed to accelerate a 15 kg gazelle at 10 m/s².


  $F =$$15 \times 10 =$$150~N$
• Why is it important to estimate speeds, accelerations, and forces involved in road vehicles?

  To understand the dynamics and safety of vehicle operation.