a computer is accelerated out a window at 8m/s/s. how much force was need for this acceleration?

Answer 1

For a rigid object, we can just use

F = ma

to relate the net force of the object and its acceleration. "Out the window" implies perpendicular to the ground, so we don't account for gravity.

When the mass of the computer in kg (not given in the problem) is m_c, and the acceleration is 8 m/s², the force in newtons is

F = m_c(8 kg) = 8m_c N/kg

If we learn the mass of the computer we can just plug it in.

A satisfying computer to accelerate out of a window might be a Macintosh II, first sold in 1987: https://support.apple.com/kb/sp193?locale=en_US

According to Apple, the PC weighed 24 lbs, which is about 10.89 kg, meaning it could be thrown by an adult human with decent acceleration. So for our problem:

F = 8m_c N/kg = 8(10.89) N = 87.12 N

Let's try accelerating a different computer through a window. The CDC 6600 was one of the first supercomputers ever created, and weighed an estimated 12,000 lbs, or 5443 kg.

When we try that in our problem, it looks like this:

F = 8m_c N/kg = 8(5443) N = 43544 N

Certain jet engines can accomplish this amount of force. If we attached a jet engine to the computer, however, we would have to add the weight of the jet engine.

A Pratt & Whitney JT3D-8A turbofan engine weighs about 2,089 kg according to this article: https://en.wikipedia.org/wiki/Pratt_%26_Whitney_JT3D

When the engine is attached to the computer, the total assembly weight (m_c+e) would then be as much as the engine and computer combined:

F = 8m_c+e N/kg = 8(5443 + 2089) N = 8(7532) N = 60256 N

The article above claims the JT3D-8A has a maximum thrust of about 76 kN (76,000 N), so it would be able to handle this important task.