An aluminium sphere is dipped into water at 10°C. If the temperature is increased, the force of buoyancy

As temperature increase there will be a slight change in the volume of aluminum and this will lead to an increase in the volume of the sphere. Due to an increase, the pressure exerted by the sphere will decrease and due to this, the volume submerged will also decrease. Due to this, the buoyant force on the sphere will decrease.