# Tension of a string on a rotating sphere and under the influence of gravity [duplicate]

I was studying about circular motion and found a topic that is apparent weight and found an equation of apparent value of g.

But I can't understand why this is written

• see the diagram-the body is rotating with our earth and the rotational motion leads to a centrifugal force in earth's frame of reference, therefore the body will experience two forces-one due to g and another due to w^2r and the resultant of two forces is effective wt. – drvrm Aug 29 '18 at 18:25
• do you mean to say that the calue of resultant is less than its constituent vectors. Why?? – Naman Vyas Aug 29 '18 at 19:25
• Related and all you need to do is use the cosine rule to get a relationship between the three sides of the vector triangle. physics.stackexchange.com/q/328618/104696 – Farcher Aug 29 '18 at 22:35

$mg-N= m\omega^2R$.
So $mg>m\omega^2R$ or $g>\omega^2R$.
Obviously $2g>\omega^2R$.
• The first equation is the second law for a body in circular motion with angular velocity $\omega$. The other two equations are just some arithmetic. The final statement provides the physical basis. Could you say which part requires additional explanation? – npojo Sep 1 '18 at 6:35