The kinetic energies of a planet in an elliptical orbit about the Sun, at positions $A, B$ and $\mathrm{C}$ are $\mathrm{K}_{\mathrm{A}}, \mathrm{K}_{\mathrm{B}}$ and $\mathrm{K}_{\mathrm{c}}$, respectively. $\mathrm{AC}$ is the major axis and $\mathrm{SB}$ is perpendicular to $\mathrm{AC}$ at the position of the Sun $S$ as shown in the figure. Then - Noon Academy

The kinetic energies of a planet in an elliptical orbit about the Sun, at positions $A, B$ and $\mathrm{C}$ are $\mathrm{K}_{\mathrm{A}}, \mathrm{K}_{\mathrm{B}}$ and $\mathrm{K}_{\mathrm{c}}$ , respectively. $\mathrm{AC}$ is the major axis and $\mathrm{SB}$ is perpendicular to $\mathrm{AC}$ at the position of the Sun $S$ as shown in the figure. Then

The kinetic energies of a planet in an elliptical orbit about the Sun, at positions $A, B$ and $\mathrm{C}$ are $\mathrm{K}_{\mathrm{A}}, \mathrm{K}_{\mathrm{B}}$ and $\mathrm{K}_{\mathrm{c}}$ , respectively. $\mathrm{AC}$ is the major axis and $\mathrm{SB}$ is perpendicular to $\mathrm{AC}$ at the position of the Sun $S$ as shown in the figure. Then

(1) $\mathrm{K}_{\mathrm{B}}<\mathrm{K}_{\mathrm{A}}<\mathrm{K}_{\mathrm{C}}$

(2) $\mathrm{K}_{\mathrm{A}}>\mathrm{K}_{\mathrm{B}}>\mathrm{K}_{\mathrm{C}}$

(3) $\mathrm{K}_{\mathrm{A}}<\mathrm{K}_{\mathrm{B}}<\mathrm{K}_{\mathrm{C}}$

(4) $\mathrm{K}_{\mathrm{B}}>\mathrm{K}_{\mathrm{A}}>\mathrm{K}_{\mathrm{C}}$

Solution:

Answer is (2)

Point $A$ is perihelion and $C$ is aphelion.

So, $V_{\text {A }}>V_{B}>V_{c}$

So, $K_{A}>K_{B}>K_{C}$

i

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