Question

# Two small balls having equal positive charges Q (coulomb) on each are suspended by two insulating strings of equal length L (metre) from a hook fixed to a stand. The whole setup is taken in a satellite into space where there is no gravity (state of weightlessness). The angle between the two strings and the tension in each string is

A
180, 14πϵ0Q24L2 N
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
B
75, 14πϵ0Q2L2 N
No worries! Weâ€˜ve got your back. Try BYJUâ€˜S free classes today!
C
120, 14πϵ0Q23L2 N
No worries! Weâ€˜ve got your back. Try BYJUâ€˜S free classes today!
D
60, 14πϵ03Q22L N
No worries! Weâ€˜ve got your back. Try BYJUâ€˜S free classes today!
Open in App
Solution

## The correct option is A 180∘, 14πϵ0Q24L2 NFree body diagram: There is a condition of weightlessness in a satellite. Therefore, mg=0. Due to electrostatic force of repulsion between the balls, the string would become horizontal. Therefore, angle between the two small balls =180∘. From free body diagram, the tension in the string will be equal to the electrostatic force of repulsion, ⇒T=Fe ⇒T=14πϵ0Q×Q(2L)2 ⇒T=14πϵ0Q24L2 N Hence, option (a) is correct answer.

Suggest Corrections
17
Related Videos
Torque on a Magnetic Dipole
PHYSICS
Watch in App
Explore more