Tag: kinematics

Questions Related to kinematics

An object is said to be in motion its position (with respect to another object)

  1. changes with time

  2. does not change with time

  3. does not change

  4. is the same as before


Correct Option: A
Explanation:

Changes with time

When a body is at rest, it is obeying :

  1. Principle of conservation of energy

  2. Newton's first law

  3. Ohm's law

  4. Newton's second law


Correct Option: B
Explanation:

Newton's first law states that; "An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force".Thus, body continues in it's state of rest as there is no external force on it,

So, option B is correct.

If a body does not change its position with respect to its surroundings, the body is said to be at rest.

  1. True

  2. False


Correct Option: A
Explanation:

The body when considered in frame of reference of surroundings, then zero relative velocity means it is at rest. So. statement is true.

In which of the following cases , the net force is zero?
I) A ball freely falling from a certain height
II) A cork floating on the surface of water
III) An object floating in air

  1. I and II only

  2. II and III only

  3. III and I only

  4. I, II and III


Correct Option: B

In the state of equilibrium
I) Net force is zero
II) Body at rest will continue to be in its state of rest
III) Body moving with uniform velocity will continue to be in its state of uniform velocity
IV) Body with linear momentum $\vec{p}$ will continue to have the same momentum $\vec{p}$.

  1. all are correct

  2. I, II, III are correct

  3. II, III, IV are correct

  4. None of these


Correct Option: A

At the starts of a motion along a line the initial velocity is u and acceleration is at. The final velocity v is 

  1. v=u+at

  2. v=u+$at^{2}$

  3. $v=u+\frac{1}{2}at^{2}$

  4. v=$at^{2}$


Correct Option: A
Explanation:

Let us assume a body that has a mass “m” and initial velocity “u”. Let after time “t” its final velocity becomes “v” due to uniform acceleration “a”. Now we know that:

Acceleration = Change in velocity/Time Taken

Therefore,  Acceleration = (Final Velocity-Initial Velocity) / Time Taken

Hence, a = v-u /t or at = v-u

Therefore, we have: v = u + at

The pendulum of a wall clock exhibits

  1. Rotatory motion

  2. Circular motion

  3. Linear motion

  4. Oscillatory motion


Correct Option: A

Symmetry of the laws of nature with respect to translation in time give rise to

  1. Conservation of linear momentum

  2. Conservation of angular momentum

  3. Conservation of cahrge

  4. Conservation of energy


Correct Option: A
Explanation:

Time translation symmetry gives rise to the conservation of energy.

Space translation symmetry gives rise to conservation of momentum.

Rotational symmetry gives rise to conservation of angular momentum.

The conservation law associated with this symmetry is the conservation of electrical charge.