not a dumb question really but to describe it, it works the same for video as it does for photos.
if you take a photo at a slow shutter speed, you are capturing one frame for a lot longer than if you were to shoot with a higher shutter speed. if you shot a photo at a shutter of 1/15 of a second of somebody running with a still camera, they would be blurry because in the amount of time the shutter was open, the subject has moved a great deal. with a fast shutter speed of something like 1/2000 of a second, that same person running would be perfectly still in the picture with no motion blur because they wouldn't move very far in the amount of time that the shutter was open.
when you take this concept to video, the frame rate of the video is the rate at how many times per second the shutter actuations will take place. so at 30fps second, the shutter will open and close 30 times in 1 second. shutter speed describes how fast that shutter opens and closes basically. with a lower shutter speed, like the 1/15, you will get very blurry, but smooth, video because all of the frames are almost blending together, whereas a shutter of 1/2000 will produce an almost choppy but very crisp looking picture. the key is to find the best balance between these for whatever your shooting. fast moving sports can use a higher shutter speed where something like a love scene can use a normal shutter speed which is usually double the frame rate.
idk if any of this will make much sense cuz its kind of all over the place. but hope it answers your question. best way to think of it is like if you were to turn your head with your eyes open and blink tem closed twice. then turn your head again at the same speed and blink as many times as you can, thats a way to compare it. slow shutter vs fast
