Q.

A quantity X is given by ε0LΔVΔt where ε0 is the permittivity of free space, L is a length, ΔV is a potential difference and Δt is a time interval. The dimensional formula for X is the same as that of                      [2001]

1 resistance  
2 charge  
3 voltage  
4 current  

Ans.

(4)

Capacitance, C=ΔqΔV=ε0AL ε0=(Δq)LA(ΔV)

  X=ε0LΔVΔt=(Δq)LA(ΔV)LΔVΔt

=(Δq)ΔVL2L2ΔVΔt=ΔqΔt=I  (current)