Assertion :In free space a uniform spherical planet of mass $M$ has a smooth narrow tunnel along its diameter. This planet and another superdense small particle of mass $M$ start approaching towards each other from rest under action of their gravitational forces. When the particle passes through the centre of the planet, sum of kinetic energies of both the bodies is maximum. Reason: When the resultant of all forces acting on a particle or a particle like object (initially at rest) is constant in direction, the kinetic energy of the particle keeps on increasing.

Both Assertion and Reason are correct and Reason is the correct explanation for Assertion

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Assertion is correct but Reason is incorrect

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Assertion is incorrect but Reason is correct

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct option is A Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
Due to the gravitational force acts on these two bodies, the speed of each component of the system increases due to loss in potential energy. It only increases, however, upto the time the particle reaches the center of planet. After that point, the net force exerted by them on each other reverses its direction. Due to this reversal, the speed of each component of the system starts decreasing and hence the kinetic energy.
Thus the kinetic energy is maximum at the center.

Suggest Corrections

Similar questions

Q. Assertion: In the equation,

y = A sin (k x - ω t)

, particle starts from its mean position

x = 0

and moves towards negative

y -

axis.
Reason: The wave corresponding to given equation is travelling towards positive

x -

direction.

Q. Assertion: Average kinetic energy in one oscillation during

SHM

of a body is

\frac{1}{4} m ω^{2} A^{2}

.
Reason: Maximum kinetic energy is

\frac{1}{2} m ω^{2} A^{2}

Assertion: A proton and an $α$ - particle are projected with the same kinetic energy at right angle to a uniform magnetic field, then the $α$ - particle will move along a circular path of smaller radius than the proton.

Reason : $B q v = \frac{m v^{2}}{r}$ holds good for the charged particle moving in a circular path in a uniform magnetic field.

Choose the most appropriate correct option:

Assertion (A) All collision of reactant molecules lead to product formation.

Reason (R) Only those collisions in which molecules have correct orientation and sufficient kinetic energy lead to compound formation.

(a) Both assertion and reason are correct and the reason is correct explanation of assertion
(b) Both assertion and reason are correct, but reason does not explain assertion.
(c) Assertion is correct, but reason is incorrect
(d) Both assertion and reason are incorrect
(e) Assertion is incorrect but reason is correct.

Q. Assertion : Two electrons of helium atom are placed in only one shell but three electrons of lithium need two shells.
Reason: A shell can have maximum

{2n}^{2}

electrons.

Join BYJU'S Learning Program