To find the net force acting on the car, we can use Newton's second law of motion, which states that the net force \( F \) is equal to the mass \( m \) of an object multiplied by its acceleration \( a \):
\[ F = m \cdot a \]
First, we need to calculate the acceleration of the car. We can use the following formula for acceleration \( a \):
\[ a = \frac{\Delta v}{\Delta t} \]
where:
- \( \Delta v \) is the change in velocity,
- \( \Delta t \) is the time taken for that change.
The car accelerates from rest (initial velocity \( u = 0 \) m/s) to a final velocity \( v = 20 \) m/s in \( \Delta t = 5 \) seconds.
Substituting the values into the acceleration formula:
\[ a = \frac{v - u}{\Delta t} = \frac{20 , \text{m/s} - 0 , \text{m/s}}{5 , \text{s}} = \frac{20 , \text{m/s}}{5 , \text{s}} = 4 , \text{m/s}^2 \]
Now that we have the acceleration, we can find the net force:
\[ F = m \cdot a = 1200 , \text{kg} \cdot 4 , \text{m/s}^2 = 4800 , \text{N} \]
Therefore, the net force acting on the car is 4800 N.
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