A boat is moving at the rate of 15.0 meters per second. It's speed is then decreased uniformly to 3.0 meters per second. It takes 4 seconds for the speed to decrease. What is the magnitude of the deceleration of the car ?

Explanation:

Given:

Initial velocity: 15 m/s

Final velocity: 3 m/s

Time: 4 s

Equation to be used is:

v = u + a*t

3 = 15 + a*(4)

a = -3 m/s^2

Since a is negative, the car is decelerating.

General note for kinematic equation questions:

These equations are built around 5 quantities:

s = displacement

u = initial velocity

v = final velocity

t = time

a = acceleration

Before starting, list down what quantities are given in the question and what quantities are asked. This will help you choose the right kinematic equation to solve the problem.

explanation:

could i give you a exaplo that could you?

f is prop to m1xm2 double m1 double force