Fourth Written Test in Science 10

What is the driving force that facilitates the slow movement of lithospheric plates?

• convection current in the mantle

• gravitational force of the moon

• magnetic force at the poles

• the force of the atmosphere

What is the source of heat in a mantle convection current?

• the crust

• the core

• the Sun

• the volcanic arcs

Which of the following will most likely happen during convection current?

• As the continental crust moves away from divergent boundary, it becomes denser than the newer continental crust.

• The hot less dense rising material spreads out as it reaches the upper mantle causing upward and sideward forces.

• The older seafloor sinks as the weight of a ridge pushes the oceanic crust towards the magma.

• Hot magma flows out of the mantle and cools down to form the new continental crust.

Which of the following statements describe a convection process?

• The hot less dense material spreads out and reaches the surface causing sideward forces.

• The hot less dense material compresses and reaches the surface causing upward forces.

• Once hot less dense particles cool down it sinks, the other less dense particles rise.

• As less dense particles cool down it sinks, the other hot less dense particles rise.

Which of the following statements best describe ridge push in convection current?

• The weight of the uplifted ridge pushes the oceanic crust towards the subduction zone.

• The weight of subducting ridge pushes the trailing slab into the subduction zone.

• The sinking force pushes tectonic plate downward.

• The sinking force pushes tectonic plate upward.

What would result if convection current will stop beneath the crust?

• The plates will still move and undergo subduction but the landmasses formed will more likely not developed.

• The tectonic plates will stop moving therefore no pushing and drifting away from each other.

• The tectonic plates will move faster causing instant formation of land masses.

• The Earth’s mantle will not undergo subduction so mountains are formed.

Which of the following processes in the convection current may result to slab pull?

• Dense material sinks that creates convection cell, with hot rising currents and cool sinking currents are regularly repeated and become a cycle.

• As the older seafloor sinks, the weight of the uplifted ridge pushes the oceanic crust towards the trench.

• The presence of a heavier subducting plate pulls down the trailing chunk into the subduction zone.

• The sinking of magma pulls down the tectonic plate at a convergent boundary.

What can you infer about the continuous movement of the lithospheric plates over the asthenosphere?

• The islands of the Philippines will become scattered all over the world.

• The continents will not be located in the same place as they are now.

• All the volcanoes in the Philippines will become inactive.

• All the continents will cease to exist.

Convection current happens in the mantle that is made up of mostly hot rocks and magma. What conclusion can you make that supports best this statement?

• The differences in the temperature at the Earth’s interior and surface cause convection currents to occur within the mantle.

• The source of heat from the core is due to the decay or breakdown of radioactive elements.

• Mantle is made up of magnetic rocks near the ridge generated by its very hot molten core.

• It is a very hot layer because of the heat generated by the core.

What do you think will happen to the convection currents in the mantle if the Earth's interior eventually cools down?

• Cooler rock near the top of the mantle begins to sink as rock that was heated near the bottom of the mantle begins to rise.

• If the interior of the Earth were too cool enough for convection currents to stop, geological processes will also stop.

• There will be ice crystals formed on the crustal plates as the temperature becomes low.

• The earth will experience global freezing as the opposite of global warming.