Two charges q1 and q2 are placed 30 cm apart as shown. A third charge q3 is moved along the arc of a circle of radius 40 cm from C to D. The change in the potential energy of the system is q34π∈0k, where k is
A
8q2
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
B
8q1
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
6q2
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
6q1
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution
The correct option is A8q2
Change in potential energy (ΔU)=Uf−Ut ⇒ΔU=14π∈0[(q1q30.4+q2q30.1)−(q1q30.4+q2q30.5)] ⇒ΔU=14π∈0[8q2q3]=q34π∈0(8q2) ∴k=8q2