The correct answer is (v-u) / t.

CONCEPT:

• Acceleration: The rate of change in velocity is called acceleration. It is denoted by a.
  • The SI unit of acceleration is m/s².
• Equation of motion: The mathematical equations used to find the final velocity, displacements, time, etc of a moving object without considering force acting on it are called equations of motion.
• V = u + at
• Where, V = final velocity, u = initial velocity, a = acceleration of body under motion, and t = time taken by the body under motion.

EXPLANATION:

From the above equation of motion:

V = u + a t

So a = (V - u)/t

• The formula for finding acceleration is (v-u) / t. So option 4 is correct.

Additional Information

• The product of velocity and time (v x t) represents the displacement of a body which represents the shortest distance between two points.
• The reciprocal of time (1 / t) represents the frequency of oscillations which gives the value of the total number of oscillations in the given time.
• The work per unit time (W / t) represents power which is the measurement of the rate of doing work.