An IC engines means an Internal Combustion engine. Here, the combustion takes place in side a chamber or a cylinder internally, hence it is known as internal combustion engine.
Combustion is the process where oxygen reacts with the fuel and it burns to produce a large amount of force and heat. In each revolution of the crank, the engine creates a power stroke when the piston goes from the bottom dead center to the top dead center.
During each power stroke, the energy released forces the piston down and the crankshaft is rotated.
a) Θ = ω₀*t + ½αt² To complete first revolution 2π rads = 0*t + ½αt² and to complete the first and second combined 4π rads = 0*t + ½α(t+0.810s)² Divide second by first: 2 = (t + 0.810s)² / t² This is quadratic in t and has roots at t = -0.336 s ← ignore and t = 1.96 s ◄ b) Use either equation from above: 2π rads = 0*t + ½α(1.96s)² α = 3.27 rad/s² ◄ Hope this helps!
So your finding acceleration first which is 30m/s divides by 6 seconds equals 5m/s^s and then multiply that by 1,400 kg and you have net force which is 7,000N