I'm comparing the "g-force" of a rocket and a race car. My answer for the race car corresponds to the answer in the book but my answer for the rocket is off by 1. The book says I need to add 1 G because the rocket is going upward. So, instead of my answer of .87 G, the correct answer is 1.87 G. Why do I need to add the 1 G because of upward motion. I'm stuck. Please help.

Question

I'm comparing the "g-force" of a rocket and a race car. My answer for the race car corresponds to the answer in the book but my answer for the rocket is off by 1. The book says I need to add 1 G because the rocket is going upward. So, instead of my answer of .87 G, the correct answer is 1.87 G. Why do I need to add the 1 G because of upward motion. I'm stuck. Please help.

Answer 1

Because the force needed to support you during your upward acceleration INCLUDES your weight.

If you were stahding on a scale and the rocket were accelerating at 0.87g, you weight would be 1.87 times your "real" weight.

Answer 2

Thanks. This explanation really helps me.

Answer 3

To understand why you need to add 1 G to account for upward motion in the rocket, let's first clarify what g-force represents.

"G-force" is a measurement of the force exerted on an object due to acceleration. It is usually measured in multiples of the acceleration due to gravity, denoted as "G" (which is approximately 9.8 meters per second squared on the surface of the Earth). So, 1 G is equal to the acceleration due to gravity on Earth.

Now, in the case of the rocket, the additional 1 G is added because it is not just experiencing the force of gravity but also undergoing an upward acceleration due to its own engines. When the rocket takes off, it accelerates upwards, opposing the downward force of gravity.

Since the acceleration due to gravity and the rocket's upward acceleration act in opposite directions, they should be summed up to find the net force acting on the rocket. Adding the 1 G accounts for the rocket's acceleration in the opposite direction of gravity.

So, to calculate the total g-force experienced by the rocket, you would add 1 G to the acceleration due to gravity. In your example, if your calculation resulted in 0.87 G (meaning the acceleration due to gravity only), you need to add 1 G to account for the upward acceleration of the rocket, resulting in a total of 1.87 G.

To summarize, when the rocket is moving upward, you add 1 G to account for the acceleration due to its own engines opposing the force of gravity. This accounts for the upward motion of the rocket and allows you to calculate the total g-force experienced.