CBSE (UGC) NET Paper 1 Questions (Part 2 of 30)

  1. A mass m (200 g) slides horizontally due to a downward force applied by a 500 g weight (as shown in figure). The velocity of the mass m (ignoring friction)

    1. increases as a function of time with constant acceleration

    2. remains constant

    3. changes with time with increasing acceleration

    4. changes with time with decreasing acceleration

  2. The O-H bonds in water molecule are polar. The molecule is symmetric and the H-O-H bond angle is approximately 107½ The dipole moment vector of the molecule is

    1. zero

    2. along the OH bond

    3. randomly oriented

    4. along the bisector of the H-O-H angle

  3. You wish to observe a small organism closely, using a convex lens. If you wish to avoid distortion of the image, you should keep the object

    1. at a distance greater than the focal length

    2. less than the focal length

    3. at twice the focal length

    4. exactly at the focal length

  4. A charged particle moving with a constant velocity enters a magnetic field perpendicular to its velocity. In which direction y an electric field should be applied to compensate the magnetic force?

    1. Along the initial velocity

    2. Perpendicular to the initial velocity and parallel to the magnetic field

    3. Perpendicular to both, the initial velocity and the magnetic field

    4. Along the magnetic field

  5. Two pendula of lengths l1 and l2 ( = 2l1) have the same period at two different locations. The accelerations due to gravity at these two locations, g1 and g2, are related by

    1. g1 = g2

    2. g1 = 2g2

    3. g2 = 2g1

    4. g2 = 4g1

  6. Water rises naturally out of an artesian well because

    1. the water has lots of dissolved gases

    2. the water table is at the ground level

    3. the water table is below the ground level

    4. the water table is above the ground level

  7. Although, we know from chemical evidence that life on Earth evolved as early as 3.5 billion years ago, the most ancient available fossils are only 0.54 billion years old. This is because

    1. acidic ocean dissolved all life forms

    2. early life forms were soft bodied

    3. rocks older than 0.54 billion years do not exist

    4. a large asteroid impact destroyed all earlier records

  8. During alpha decay of a radioactive atom, the mass number reduces by 4 units and the atomic number decreases by 2 units. How many alpha particles will be generated during the decay of a 238, 92U atom to a 206 − 82 Pb atom

    1. 8

    2. 16

    3. 10

    4. 5

  9. Depletion of ozone layer and formation of ozone hole in polar regions is a phenomenon occurring in the

    1. troposphere

    2. mesosphere

    3. stratosphere

    4. thermosphere

  10. Sea levels are predicted to rise in the near future mainly due to

    1. sinking of landmass

    2. increased rainfall

    3. gravitational pull of the moon

    4. melting of glaciers