Two small spheres attract each other with a force of when their centres are apart

PHYSICS · Single correct · A Level · Physics · Fields and their consequences · Fields and their consequences

Problem

Two small spheres attract each other with a force of

0.60\,\text{N}

when their centres are

30\,\text{cm}

apart. Keeping their masses unchanged, at what separation will the force be

0.15\,\text{N}

? (a)

45\,\text{cm}

(b)

120\,\text{cm}

(c)

60\,\text{cm}

(d)

15\,\text{cm}