अपवर्तनांक μ = 1.54 की समतल काँच की सतह पर अध्रुवित प्रकाश आपतित होता है। आपतन कोण कितना होना चाहिए ताकि परावर्तित और अपवर्तित किरणें एक-दूसरे के लंबवत हों?

The arrival of which commission in India triggered widespread protests, including mass hartals across the country in 1928?

Which of the following leaders was instrumental in initiating and leading India’s struggle for independence?

Which of the following viceroys of India is associated with the 'Ilbert Bill' controversy?