Earth Science MCQs (Part 15 of 21)

  1. The Earth would have one side always facing the sun if the

    1. Earth went around the sun but did not rotate.

    2. period of rotation and revolution were equal

    3. period of rotation was half that of the period of revolution

    4. period of rotation was twice that of the period of revolution.

  2. Assuming the altitude of all the continents to be the same, the range of temperature would be greatest at the

    1. centre of the largest mass at high latitude

    2. centre of the largest mass at low latitude

    3. western part of the largest mass in southern hemisphere

    4. eastern part of the largest mass in northern hemisphere

  3. Ocean surface currents are mainly caused by

    1. wind

    2. tides

    3. salinity differences

    4. density differences

  4. The stress at which rocks begin to strain permanently is the

    1. yield strength

    2. ultimate strength

    3. fracture strength

    4. tensile strength

  5. A scientist runs an experiment to test the deformation behaviour of a rock in the atmospheric condition and plots the compressive stress (s) as a function of strain (e). She finds that

    1. s a 1/e

    2. s a e

    3. s a e2

    4. s a 1/e2

  6. In the Himalayan mountain belt one can find abundant

    1. normal faults and folds

    2. thrusts and folds

    3. strike-slip faults and bending of rock strata

    4. gravity-induced sag structures

  7. Natural earthquakes are generated due to

    1. plastic flow of rocks and release of plastic strain energy

    2. folding of rock layers

    3. sudden release of elastic strain energy during fracture propagation

    4. sudden release of viscous strain accumulated in rocks.

  8. The Mohorovicic discontinuity below the Himalayan orogen is at a depth greater than that below the Indian Craton. This is because of:

    1. isostatic mass adjustment

    2. lateral density variation

    3. upwelling material below the Indian craton

    4. less tectonic activity in the Himalayan region.

  9. P-wave shadow zones recorded by seismologists indicate the boundary between the

    1. lower and upper crusts

    2. inner core and outer core

    3. lower mantle and outer core

    4. transition zone and lower mantle

  10. In the mantle, heat flow on long time scales takes place by convection. With increase in the Rayleigh number, the mantle convection would

    1. stop

    2. become vigorous

    3. propagate laterally

    4. be pulsating