In my first post I failed to answer the second part of your query regarding the shutter speed. The convention wisdom to prevent hand held blur of stationary subjects is 1/focal length x crop factor which in this case would be 1/80 second.

However don't use that guideline as a standard. First, it is only intended for static images. For moving subjects the shutter speed will have to be much faster to capture an image without motion blur. Second, lenses with image stabilization will allow you to capture sharp static images hand held at much lower shutter speeds. Cameras that also have in-body image stabilization (IBIS) will allow you to capture those same images at significantly slower shutter speeds.

In addition your skills as a photographer, how you stand, how you breathe, how you hold and brace your camera, and how you depress the shutter button will all affect how slow a shutter speed can be and still give you sharp results. However all of these techniques will have less impact on subjects that are moving.

Shutter speed is part of the exposure triangle with aperture and ISO. Selecting a shutter speed in relation to the ISO and aperture to get you the desired results is part of the creative process.

Slower shutter speeds can allow you to use creative blur to, for example, give a sense of motion by blurring a ball that's being pitched to a batter in a baseball game. It can also be used to give a milky or cotton like quality to moving water that many people like.

Emphasizing the impact of Image Stabilization, it really throws the 1/focal-length "rule" out the window. Although, that rule is worth remembering when considering the impact or 'support' of the IS. If you find you need about 1/100 sec to reliable get sharp (steady) focus with an unstabilized 50mm lens on a crop sensor, you should test your IS-enabled lens at 1- and 2- and 3-stops slower to get your own sense of your abilities using the IS. 1-stop down from 1/100sec is 1/50sec, 2-stop is 1/25sec and 3-stop 1/12sec. Even with IS-support and a wider lens than 50mm, I personally can barely / rarely hold a camera / lens steady below 1/15sec.

As I understand it:
Exposure is determined by aperture + shutter speed + iso. Focal length is not part of the equation.
Focal length is “fixed” by the physical properties of the lens. 50mm is 50mm.
Using the lens on a DX camera (“crop factor”), reduces the angle of view, capturing a smaller area of the scene. The resulting “cropped” photo gives you the illusion of increased reach.

If that’s not the case, someone please feel free to correct me.

I guess I have to learn to type faster.
Several others responded while I was diddling along.

Focal length of a lens does not change. Your 50 mm lens is still 50 mm no matter what type of camera it's mounted on. However, when you put that lens on a crop sensor camera which has a smaller sensor area, as a result of the smaller lens image circle it gives you the impression that your camera has zoomed in a bit compared to a full-frame camera and the focal length has changed. But in fact it is not changed. 50 mm is always 50 mm. What has happened is that the smaller sensor has changed the angle of view and is giving you a full-frame cameras view equivalent to 80 mm. That is often referred to as the crop factor, and for Canon cameras the crop factor is 1.6. When you multiply 50 mm times 1.6 you get the equivalent full frame angle of view of 80 mm.