Question

What is the acceleration of a train moving west at a velocity of 15 m/s that slows to 5 m/s in 20 seconds?

Answer 1

Answer:

Acceleration, a = -0.5m/s² West

Explanation:

Given the following data;

Initial velocity = 15m/s²

Final velocity = 5m/s²

Time = 20 secs

To find the acceleration

In physics, acceleration can be defined as the rate of change of the velocity of an object with respect to time.

This simply means that, acceleration is given by the subtraction of initial velocity from the final velocity all over time.

Hence, if we subtract the initial velocity from the final velocity and divide that by the time, we can calculate an object’s acceleration.

Mathematically, acceleration is given by the equation;

$Acceleration (a) = \frac{final \; velocity - initial \; velocity}{time}$

$a = \frac{v - u}{t}$

Where,

a is acceleration measured in $ms^{-2}$

v and u is final and initial velocity respectively, measured in $ms^{-1}$

t is time measured in seconds.

Substituting into the equation, we have

Acceleration, a = (5 - 15)20

Acceleration, a = -10/20

Acceleration, a = -0.5m/s²

Therefore, the train is decelerating at a rate of -0.2m/s²