# physics

A uniformly charged insulating rod of length 14 cm is bent into the shape of a semicircle. if the rod has a total charge of -7.5 C. find the magnitude and direction of the electric field at the center of the semicircle.

I'm not sure where to start or what to do. what formula is used?

1. 👍
2. 👎
3. 👁
1. You know the formula for E from any segment dL (dL contains dq). You have to integrate around the semicircle to get E. Actually, it is easy as a vector, because you use arguments of symettry to just integrate the components of E directed along the axis of symettry, as the E perpendicular will cancel out. You will be integrating a sin/cos function of the angle, and it becomes trivial.

1. 👍
2. 👎
👤
bobpursley

## Similar Questions

1. ### Calculus

A wire 60 cm long is to be cut into two pieces. One of the pieces will be bent into the shape of a square and the other into the shape of an equilateral triangle, as shown in the diagram below: a diagram showing a 60 cm wire cut

2. ### college physics

A rod 14.0 cm long is uniformly charged and has a total charge of -20.0 µC. Determine the magnitude and direction of the electric field along the axis of the rod at a point 36.0 cm from its center. N/C

3. ### physics

A thin rod has a length of 0.25 m and rotates in a circle on a frictionless tabletop. The axis is perpendicular to the length of the rod at one of its ends. The rod has an angular velocity of 0.33 rad/s and a moment of inertia of

4. ### Physics

A neutral ball is suspended by a string. A positively charged insulating rod is placed near the ball, which is observed to be attracted to the rod. Why is this? 1. The ball becomes negatively charged by induction. 2. The string is

1. ### Science

A rod (length = 2.0 m) is uniformly charged and has a total charge of 40 nC. What is the magnitude of the electric field at a point which lies along the axis of the rod and is 3.0 m from the center of the rod in N/C?

2. ### physics

A uniformly charged insulating rod of length 19.0 cm is bent into the shape of a semicircle. The rod has a total charge of −8.50 ìC. Find the electric potential at O, the centre of the semicircle.

3. ### physics

A uniformly charged insulating rod of length 13.0 cm is bent into the shape of a semicircle as shown in the figure below. The rod has a total charge of -7.50 µC. Find the magnitude and direction of the electric field at O, the

4. ### PHYSICS

A rod 14.0 cm long is uniformly charged and has a total charge of -20.0 µC. Determine the magnitude and direction of the electric field along the axis of the rod at a point 36.0 cm from its center. N/C

1. ### Physics (please check!)

A positively charged light metal ball is suspended between two oppositely charged metal plates on an insulating thread as shown below. After being charged once, the plates are disconnected from the battery. Describe the behavior

2. ### PHYSICS

A rod 14.0 cm long is uniformly charged and has a total charge of -20.0 µC. Determine the magnitude and direction of the electric field along the axis of the rod at a point 36.0 cm from its center. N/C toward the rod away from

3. ### Math

You have a wire that is 35 cm long. You wish to cut it into two pieces. One piece will be bent into the shape of a square. The other piece will be bent into the shape of a circle. Let A represent the total area of the square and

4. ### PHYSICS

A rod 14.0 cm long is uniformly charged and has a total charge of -20.0 µC. Determine the magnitude and direction of the electric field along the axis of the rod at a point 36.0 cm from its center. N/C