Answer:
1. the electric potential energy of the electron when it is at the midpoint is - 2.9 x J
2. the electric potential energy of the electron when it is 10.0 cm from the 3.00 nC charge is - 5.04 x J
Explanation:
given information:
= 3 nC = 3 x C
= 2 nC = 2 x C
r = 50 cm = 0.5 m
the electric potential energy of the electron when it is at the midpoint
potential energy of the charge, F
F = k
where
k = constant (8.99 x )
electron charge, = - 1.6 x C
since it is measured at the midpoint,
r =
= 0.25 m
thus,
F =
= k + k
= ()
= (8.99 x )( - 1.6 x )(3 x +2 x )/0.25
= - 2.9 x J
the electric potential energy of the electron when it is 10.0 cm from the 3.00 nC charge
= 10 cm = 0.1 m
= 0.5 - 0.1 = 0.4 m
F = k + k
= (+)
= (8.99 x )( - 1.6 x )(3 x /0.1+2 x /0.4)
= - 5.04 x J
Answer:
105 m/s
Explanation:
Given that the speed of train A, = 45 m/s from west to east.
Speed of train B, = 60 m/s from east to west.
Train B is moving in the opposite direction with respect to the speed of train A. Assuming that the speed from east to west direction is positive.
So, the speed of train A from east to west= - 45 m/s
The speed of train B w.r.t train A m/s
Hence, the speed of train B w.r.t train A is 105 m/s from east to west.
As the ball is moving in air as well as we have to neglect the friction force on it
So we can say that ball is having only one force on it that is gravitational force
So the force on the ball must have to be represented by gravitational force and that must be vertically downwards
So the correct FBD will contain only one force and that force must be vertically downwards
So here correct answer must be
<em>Diagram A shows a box with a downward arrow. </em>