Two stars are 10 light years away from the earth

PHYSICS · Single correct · A Level · Physics · Waves · Waves

Problem

Two stars are 10 light years away from the earth. They are seen through a telescope of objective diameter 30 cm. The wavelength of light is

600 \text{ nm}

. To see the stars just resolved by the telescope, the minimum distance between them should be (1 light year

= 9.46 \times 10^{15} \text{ m}

) of the order of: (1)

10^8 \text{ km}

(2)

10^{10} \text{ km}

(3)

10^{11} \text{ km}

(4)

10^6 \text{ km}