Explain the term Colliding beams?

When a pair of particles is generated or interacts in certain ways, they are said to be "entangled". What does this mean?           Measurements made on these particles are predictable.       Measurements made on these particles are unpredictable.       Particles will move parallel to each other in a corkscrew way.       Measurements made on these particles will be correlated.

4. A long line charge A (charge per unit length) is located at axis of a toroidal coil of rectangular cross section, as shown in Fig. 4. The inner radius of the coil is a, outer radius a + w, and height h, which carries a total of N tightly-wound turns and current I. (a) Find the electromagnetic momentum p of this configuration. Figure 4 (b) Now the current in the toroid is turned off, quickly enough that the line charge does not move appreciably as the magnetic field drops to zero. Find the induced electric field at the center of the toroid. Here, you can assume that w and h are both much less than a. Hint: to find the induced electric field exploit the analogy between Faraday (induced) electric fields and magnetostatic fields of a circular current loop.

Electrons passes undeviated through crossed electric and magnetic fields. If E = 5 × 10¹ N/c and B = 4 × 10-4 Wb/m² find the velocity of electrons.