Consider a planet whose mass and radius are both twice the mass and radius of Earth. The acceleration due to gravity on the surface of the planet is 'n' times that on Earth. The value of n is:
n an alloy, lead and tin are in the ratio of 2 : 3. In the second alloy, the ratio of same elements is 3 : 4. If equal quantities of these two alloy are mixed to forma new alloy, then what will be the ratio of these two elements in the new alloy?