Physics 2012 JAMB Past Questions - Question 7: A car starts from rest and moves with a uniform acceleration of 30ms-for 20s.Calculate the distance covered at the end of the motion .

Correct Answer

A

Explanation

the graph of the motion is shown below:v = u +at= 0 + 30 x 20= 600mlsDistance traveled= Area of graph1/2 bh = 1/2 x 20 x 600= 600m = 6km
To calculate the distance covered by the car at the end of the motion, we can use the equation:

\[ s = ut + \frac{1}{2}at^2 \]

Where:
- \( s \) is the distance covered
- \( u \) is the initial velocity (which is 0 in this case since the car starts from rest)
- \( a \) is the uniform acceleration
- \( t \) is the time taken

Given that the uniform acceleration is 30 m/s² and the time taken is 20 seconds, we can substitute these values into the equation:

\[ s = 0 \cdot 20 + \frac{1}{2} \cdot 30 \cdot (20)^2 \]

Simplifying the equation:

\[ s = 0 + \frac{1}{2} \cdot 30 \cdot 400 \]

\[ s = 0 + 15 \cdot 400 \]

\[ s = 6000 \]

Therefore, the car covers a distance of 6000 meters at the end of the motion.