A person used force (F), shown in figure to move a load with cons

Subject

Physics

Class

NEET Class 12

Test Series

Take Zigya Full and Sectional Test Series. Time it out for real assessment and get your results instantly.

Test Yourself

Practice and master your preparation for a specific topic or chapter. Check you scores at the end of the test.
Advertisement

 Multiple Choice QuestionsMultiple Choice Questions

1.

Two spheres of same size, one of mass 2 kg and another of mass 4 kg are dropped simultaneously from the top of Qutab Minar  ( height ≈ 72 m ). When they are 1 m  above the ground the two spheres have the same

  • momentum

  • kinetic energy

  • potential energy

  • acceleration


2.

The moment of inertia of a rod about an axis through its centre and perpendicular to it is 112 ML2 ( where M is the mass and L, the length of the rod). The rod is bent in the middle so that the two halves make an angle of 60°. The moment of inertia of the bent rod about the same axis would be

  • 148 ML2

  • 112ML2

  • 124 ML2

  • ML283


3.

The voltage of clouds is 4 x 10 volt with respect to ground. In a lightening strike lasting 100 msec, a charge of 4 coulombs is delivered to the ground. The power of the lightning strike is

  • 160 MW

  • 80 MW

  • 20 MW

  • 500 MW


4.

For inelastic collision between two spherical rigid bodies

  • the total kinetic energy is conserved

  • the total potential energy is conserved

  • the linear momentum is not conserved

  • the linear momentum is conserved


Advertisement
Advertisement

5.

A person used force (F), shown in figure to move a load with constant velocity on surface. Identify the correct surface profile.

    


C.

First a force is used to move the body when it has to be more than the static friction. Then the
body starts moving and is getting accelerated. Then 

          

suddenly the force is decreased to match the kinetic friction. The body then moves with a constant velocity. 

            Force  > μs · N

Constant acceleration, velocity increases proportionately with time. Then suddenly force applied is just equal to  μkN. It is just sufficient to cancel friction. Whatever be the earlier maximum velocity attained will be continued.


Advertisement
6.

Assertion:  A judo fighter in order to throw his opponent on to the mat tries to initially bend his opponent and then rotate him around his hip. 

Reason: As the mass of the opponent is brought closer to the fighter's hip, the force required to throw the opponent is reduced.

  • If both assertion and reason are true and reason is the correct explanation of the assertion

  • If both assertion and reason are true but reason is not the correct explanation of the assertion

  • If assertion is true, but reason is false

  • Both assertion and reason are false statements


7.

Assertion: A man in a closed cabin which is falling freely does not experience gravity.

Reason: Inertial and gravitational mass have equivalence.

  • If both assertion and reason are true and reason is the correct explanation of the assertion

  • If both assertion and reason are true but reason is not the correct explanation of the assertion

  • If assertion is true, but reason is false

  • Both assertion and reason are false statements.


8.

A boat at anchor is rocked by waves whose crests are 100 m apart and velocity is 25 m/sec. The boat bounces up once  in  every

  • 2500 s

  • 75 s

  • 4 s

  • 0.25 s


Advertisement
9.

By sucking through a straw, a student can reduce the pressure in his lungs to 750 mm of Hg ( densiy = 13.6 g/cm3). Using the straw, he can drink water from a glass upto a maximum depth of

  • 10 cm

  • 75 cm

  • 13.6 cm

  • 1.36 cm


10.

A stone thrown into still water, creates a circular wave pattern moving radially outwards. Ifr is the distance measured from the centre of the pattern, the amplitude of the wave varies as

  • r1/2

  • r-1

  • r2

  • r3/2


Advertisement