Two substances of densities $$\rho$$₁ and $$\rho$$₂ are mixed in equal volume and their relative density is 4. When they are mixed in equal masses, relative density is 3. The values of $$\rho$$₁ and $$\rho$$₂ respectively, are

A car starts from Bengaluru, goes 50 km in a straight line towards South, immediately turns around and returns to Bengaluru. The time taken for this round trip is 2h. The magnitude of the average velocity of the car for this round trip

"The sum of emf's and potential differences around a closed loop equals zero" is a consequence of

A student measures certain lengths using a meter scale having least count equal to 1 mm. Which one of the following measurement is more precise?