Part of the show What's the point of eyebrows?
DavidWorley94, via twitter asked:
If you jump down a hole that went through the centre of the planet, would you fall out the other end or stay in the middle?
Andrew: - You would absolutely fall out the other end. So you'd accelerate all the way until you got to the centre and then youíd decelerate all the way until you got to the other end and then you would come to a graceful stop, just as you got to the hole in Australia if you jumped in in the UK, and that would be that.
Chris: - And you then oscillate presumably?
Andrew: - If you didnít actually manage to stop yourself when you got to the other end, and hopefully be prepared and you would, you would oscillate backwards and forwards forever.
Chris: - Some people say with the same rate as if you had a satellite doing an orbit around the earth.
Andrew: - Well it depends slightly on exactly what orbit you put it into. If I remember correctly, itís about 42 minutes, the period of oscillation.