EK$14$ Aj$$j$3$: A na$-$etinye $$k$$ eletrik nke radius rn n'ime akpa igwe anagh$$ agba nchara nwere okirikiri nwere radius rc ma na$-$ebute okpom$$k$$ na $$n$$ego R $($W$/$m$3).$ A na$-$emikpu ak$$r$$ngwa kpo oku n'ime mmiri nke nwere ebe na$-$esi esi mmiri T$,$ na $$n$$g$$ nnyefe okpom$$k$$ b$$ ho$.($a$)$ Malite site na nguzozi ike n'ozuzu ma na$-$egosi $$n$$d$$k$$ala$,$ wep$$ta okwu maka nkesa okpom$$k$$ na ikpo $$k$$ na ikpe ah$$ ma $$ b$$r$$ na ihe nd$$ na$-$ekpo $$k$$ nke ikpo $$k$$ na ikpe ah$$ b$$ k na ke$,$ n'otu n'otu $($W $/$ m$.$K$).($b$)$ Olee ot$$ okpom$$k$$ d$$ n'elu nke sphere na okpom$$k$$ na$-$ebufe gburugburu ga$-$agbanwe ma $$ b$$r$$ na a na$-$ekpuchi ebe ah$$ na ihe onwunwe nwere thermal conductivity k na$-$ejigide radius mp$$ta nke ri$.$