Acceleration

• What is acceleration defined as?

  Acceleration is the rate of change of velocity.
• How is acceleration related to velocity and time?

  It is the amount that velocity changes per unit time.
• What is the formula for calculating average acceleration?

  $\alpha =$$\frac{v - u}{t}$
• In what units is acceleration measured?

  Acceleration is measured in metres per second squared (m/s²).
• What does a negative acceleration indicate?

  A negative acceleration indicates that an object is decelerating.
• What is the average acceleration of a car that accelerates from rest to 28 m/s in 8.0 seconds?

  The average acceleration is $3.5 \text{ m/s}^2$.
• How do you calculate the average acceleration of a car that takes 25 seconds to accelerate from 20 m/s to 30 m/s?

  • Final velocity, v = 30 m/s
  • Initial velocity, u = 20 m/s
  • Change in velocity, v - u = 30 - 20 = 10 m/s
  • Time taken, t = 25 s
  • Average acceleration, $\alpha =$$\frac{10 \text{ m/s}}{25 \text{ s}} =$$0.4 \text{ m/s}^2$
• What are some typical accelerations for different methods of travel?

  • Running: 2 m/s²
  • Family car: 1-7 m/s²
  • Motorbike: 1-10 m/s²
  • Rollercoaster: 30-60 m/s²
  • Formula One car: 49 m/s²
• What is the acceleration due to Earth's gravity?

  The acceleration due to Earth's gravity is $10 \text{ m/s}^2$.
• How does acceleration differ when an object is speeding up versus slowing down?

  Speeding up indicates positive acceleration, while slowing down indicates negative acceleration (deceleration).