What is the force in pounds that acts on him during the launch phase of this ride?

Question

The Kingda Ka roller coaster in New Jersey is the world's tallest ride of its kind. As the passenger cars are launched from rest at the start, they are accelerated uniformly to a speed of 57 m/s (128 mph) in just 3.5 s. (Assume the cars are launched in the positive horizontal direction. Indicate the direction with the sign of your answer where appropriate.)

What is the acceleration experienced by passengers on this ride in g's? 

If a certain passenger has a mass of 76 kg, what is the force in newtons that acts on him during the launch phase of this ride? 

Answer 1

The acceleration is the final velocity minus the initial velocity divided by the time. The initial velocity is zero, so the acceleration is 57 m/s / 3.5 s = +16 m/s² or 16/9.8 = 1.6 g's. The force in newtons is mass times acceleration or

F = m x a = 76kg x 16 m/s² = 1216 N or 1200 N to 2 significant figures.