A particle A of mass 6 kg is connected by a light in extensible string passing over a fixed smooth pulley to a light smooth moveable pulley B. Two particles C and D of masses 2 kg and 1 kg are

connected by a light in extensible string passing over the pulley B. When the system is moving

freely find the acceleration of the 1 kg mass and the tension in the strings.​

That big glowy thing in the sky is called the sun

D. the index of refraction of the second medium is lower.

Answer;

hot magma rises and pushes up toward the lithosphere, and as it cools it cycles back down toward the core to be heated again.

explanation; convection currents are the circular pathways taken by a fluid that enhances heat transfer by the process known as convection which occurs in fluids.convection currents transfer heat from one place to another by mass motion of a fluid. earth mantle is in a semi-liquid state and behaves like any other fluid, rising up from the bottom of the mantle after becoming hotter and less dense from heat of the earth's core, as the rock loses heat into the earth's crust it becomes cooler and more dense, then sinking back down to the core, then repeating the cycle.