Question

A car of mass 400kg starts from rest and attains a velocity of 30m/s in 5s
(i) find its acceleration
(ii)calculate the resultant force
(iii) How far did the car travel in 5s

Answer 1

(i) To find the acceleration, we can use the equation:

acceleration = (final velocity - initial velocity) / time

Given that the initial velocity is zero and the final velocity is 30 m/s, and the time is 5 seconds, we can plug these values into the equation:

acceleration = (30 m/s - 0 m/s) / 5 s = 6 m/s^2

So, the acceleration of the car is 6 m/s^2.

(ii) To calculate the resultant force, we can use Newton's second law of motion, which states that force equals mass times acceleration:

force = mass * acceleration

Given that the mass of the car is 400 kg and the acceleration is 6 m/s^2, we can plug in these values:

force = 400 kg * 6 m/s^2 = 2400 N

So, the resultant force acting on the car is 2400 N.

(iii) To find how far the car traveled in 5 seconds, we can use the equation for distance traveled during constant acceleration:

distance = (initial velocity * time) + (0.5 * acceleration * time^2)

Given that the initial velocity is 0 m/s, the time is 5 seconds, and the acceleration is 6 m/s^2, we can plug these values into the equation:

distance = (0 m/s * 5 s) + (0.5 * 6 m/s^2 * (5 s)^2) = 0 + 75 m

So, the car traveled a distance of 75 meters in 5 seconds.