Answer:
The answer is the kinetic energy of sled B after it crash is 6439j.
Answer:
Electric Field a the centre
Explanation:
<u>Given:</u>
Total charge on the semicircle =Q
Radius of the semicircle=R
Let consider a elemental charge on the semicircle at an angle
with the horizontal. Since the The charge distribution is symmetrical about y axis so the there will symmetrical charge on other side. The horizontal component will cancel out each other and vertical component will get added so let dE be the electric Field due to elemental charge
Let
be the charge per unit length such that

Total Electric Field at the centre

integrating 0 to 


So the Electric field at the centre is calculated.
Answer;
26.45cm
See attached file for explanation