Unfortunately, this is not the case. Women are woefully underrepresented in physics programs. Here’s the 2017 graduation numbers:
[ul][li]BS - 1404 women (20%); 5465 men (80%)[/li]
[li]MS - 391 women (24%); 1230 men (76%)[/li]
[li]PhD - 296 women (18%); 1395 men (82%)[/ul][/li]Source: US Department of Education, “Bachelor’s, master’s, and doctor’s degrees conferred by postsecondary institutions, by sex of student and discipline division”
As for an admissions boost, that probably depends a great deal on the college in question. It may help more at a college like Rose-Hulman (75% male) than at a women’s college like Smith or Bryn Mawr, for example.