HT) Calculate the resultant force which is required to uniformly decelerate a car of mass 2000 kg to rest from an initial velocity of 20 m/s over a period of 10 seconds.40 kN4000 kN4 kN400 kNCHECK YOUR ANSWERS

To calculate the resultant force, we first need to calculate the deceleration of the car.

Step 1: Calculate deceleration Deceleration is the change in velocity over time. In this case, the car is going from 20 m/s to 0 m/s over 10 seconds. So, the deceleration is (0 - 20) / 10 = -2 m/s². The negative sign indicates that this is a deceleration.

Step 2: Calculate force Next, we use Newton's second law of motion, which states that force equals mass times acceleration (or in this case, deceleration). The mass of the car is 2000 kg and the deceleration is -2 m/s². So, the force is 2000 kg * -2 m/s² = -4000 N.

The negative sign indicates that this is a force applied in the opposite direction of motion, which makes sense because we're decelerating the car to a stop.

So, the resultant force required to decelerate the car is 4000 N. However, the options are given in kN, so we need to convert N to kN.

1 kN = 1000 N, so 4000 N = 4 kN.

Therefore, the correct answer is 4 kN.