Question
Two positive charges of magnitude \(q\) and \(2 q\) are fixed as shown. At which position is the electric field, due to these charges, equal to zero?
▶️Answer/Explanation
Ans:B
At position A and D electric can never be zero.
At B distance from 2q is much more then c and magnitude is also 2 times so more possibility of cancel out each other because At C distance from q is lower and magnitude is also smaller in compare to 2q so there is more chance that $E_2q$ will ore domniate over $E_q$
Question
Three point charges, \(+Q,+Q\) and \(-Q\), are fixed at the three corners of a square. What is the direction of the electric field at the fourth corner?
▶️Answer/Explanation
Ans:B
A particle has charge and mass. Which types of field cause a force to be exerted on the particle when it is moving in the direction of the field?
A. Electric, gravitational and magnetic fields
B. Electric and magnetic fields only
C. Gravitational and magnetic fields only
D. Electric and gravitational fields only
Answer/Explanation
Answer – D
Electric field due to its charge
Gravitational field due to its mass.
An electron is held close to the surface of a negatively charged sphere and then released. Which describes the velocity and the acceleration of the electron after it is released?
Answer/Explanation
Answer – D
Since it is a negatively charged sphere and not a plate hence the field will decrease as a square of distance. So theoretically the electron will go through a pretty huge force and hence acceleration and will aquire a velocity. But as the field drops the force and hence the acceleration will drop too. So through the velocity will keep increasing the rate of increase of velocity will keep going down
Four point charges of equal magnitude W, X, Y and Z are each fixed to a corner of a square.
W is a positive charge and X is a negative charge. The arrow shows the direction of the resultant electric field at the centre of the square. What are the correct signs of charge Y and of charge Z?
Answer/Explanation
Answer -D
