This is a free, peer-reviewed textbook used by universities. It covers almost every topic in A Level Physics with the same rigor. Z-Library / Archive.org:
Most "free PDF download" sites (fileshare, mediafire, bitty, etc.) are not vetted. In 2023-2024, cybersecurity firms reported a 350% increase in educational PDFs being used as Trojan horse vectors. You might download "Physics.pdf" and instead install a keylogger that steals your college application passwords.