A block of mass is taken to a tunnel below the Earth’s surface

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

Problem

A block of mass

20\,\text{kg}

is taken to a tunnel

1\,\text{km}

below the Earth’s surface. Take Earth’s radius

R = 6.4\times10^{6}\,\text{m}

and

g = 9.8\,\text{m\,s}^{-2}

at the surface. What is the weight of the block at that depth? (a)

200\,\text{N}

(b)

196\,\text{N}

(c)

176\,\text{N}

(d)

165\,\text{N}