Answer:
7.2 × 10^5 N
Step-by-step explanation:
The first step is to convert 1400 km/hr to m/s
= 1,400×1000/3600
= 1,400,000/3600
= 388.88 m/s
The acceleration can be calculated as follows
a= v-u/t
= 388.88/2.1
= 185.18
Therefore the required net force can be calculated as follow
= 388.88 × 185.18
= 7.2 × 10^5 N