That is not the correct value for a, you must divide f by m giving you .469m/s2
From there divide the original 99.1 m/s by .469m/s^2 to give you your time.
A de-orbit burn, similar (but not the same) to that presented in the previous math problem, has been performed. During this de-orbit burn a pre-calculated ∆V (delta V, change in velocity) of 99.1 meters per second will be used to decrease the Shuttle’s altitude from 222.5 miles to 60 miles at perigee. The Shuttle’s Orbital Maneuvering System (OMS) engines provide a combined thrust force of 53,000 Newtons. The Shuttle had a mass of 113,000 kg when fully loaded.
What is the difference between the Shuttle’s mass and weight? An object’s mass does not change from place to place, but an object’s weight does change as it moves to a place with a different gravitational potential. For example, an object on the moon has the same mass it had while on the Earth but the object will weigh less on the moon due to the moon’s decreased gravitational potential. The shuttle always has the same mass but will weigh less while in orbit than it does while on Earth’s surface.
Calculate how long a de-orbit burn must last in minutes and seconds to achieve the Shuttle’s change in altitude from 222.5 miles to 60 miles at perigee with a ∆V of 99.1m/s. Use the equations and conversions provided below to find the required burn time.
Equation Method:
Newton’s Second Law: F = ma
Where:
a = acceleration is in meters per second per second (m/s2)units
F = force is in Newtons (1 N = 1kg m/s2 )
M = mass is in kg units
Equation that defines average acceleration, the amount by which velocity will change in a given amount of time: a = ∆V/t
Rearranging the acceleration equation above to find the time required for a specific velocity change given a specific acceleration, where t = ∆V/a
∆V = change in velocity in meters per second (mps)
a = acceleration is in meters per second per second, m/s2
t = required time in seconds
My work:
f= 53,000 Newtons
m= 113000kg
a= 99.1 meters/second
Question is: How do I calculate it when the problem occurs that I have already solved Newton's second law, I am lost where to go after that.
1 answer
1 answer