What will be the impact if earth stops rotating?
Please read below.
If earth stops rotating there may be only a marginal impact on gravity as centrifugal force, if any, acting on objects won't be there an hence gravitational force may rather increase marginally.
However, the fact is that there may be more profound impact on other things, some of which are listed below.
(1) There will not be any day and nights on earth. It may be all perpetual day or perpetual night. The only difference may be that when moon is there in night sky, it may be a little better.
(2) Where, we will have perpetual day, it may be very hot and where we will have perpetual night, we may have very cold. This may cause strong wind movements and consequent impact on weather and climate.
(3) The above may have profound affect on life on earth and in that case evolution of life, agriculture and plant growth may drastically differ between places with perpetual days and perpetual nights including portions of sea or oceans.
(4) There may also be some impact on high and low tides.