Is the force of gravity stronger on a piece of iron than on a piece of wood if both have the same mass?

Why does a ship made of iron float while a piece of iron sinks in water?

A rigid bar of mass M is supported symmetrically by three wires each of length 1. Those at each end are of copper and the middle one is of iron. The ratio of their diameters, if each is to have the same tension, is equal to ......

Why does a diamond shine more than a glass piece cut to the same shape? (AS_(7)

A rigid bar of mass 15 kg is supported symmetrically by three each 2.0 m long. Those at each end is to copper and the middle one is of iron. Determine the ratios of their diameters if each is to have the same tension.

A piece of iron when placed on a block of wood, this makes the wood to float lower in the water. If the iron piece is suspended beneath the wood block, would it float at the same depth? Or lower or higher? You know that pressure difference at different levels inside the liquid causes buoyancy.

Explain why, an optical pyrometer (for measuring high temperatures) calibrated for an ideal black body radiation gives too low a value for the temperature of a red hot iron piece in the open, but gives a correct value for the temperature when the same piece is in the temperature when the same piece is in the furnace.

Imagine a new planet having the same density as that of earth but it is 3 times bigger than the earth in size. If the acceleration due to gravity of the surface of earth is g and that on the surface of the new planet is g', then ..........