You can calculate the speed of the ball by the distance it travels divided by the time.

Length of string = 2m

Circumference of circle = 2*radius*π = 4*pi = ~12.6 meters

Speed = distance/time = 12.6m/2s = 6.28m/s

Acceleration = V²/R where the velocity at any one point is the same as the speed.

acceleration = (6.28)²/2 = ~19.72m/s²

**Given that,**

A charged particle enters a magnetic field with an angle theta .

If

**We know that, **

If the angle is 90° then the charged particle enters perpendicular to the B.

B is magnetic field.

The charged particle will be follow of the circular path.

If the angle is greater than 0 and less than 90° then the charged particle will be show the helical path.

**Hence, This is required answer.**

Kinetic energy equation is given:

Substituting our known variables, we get:

KE = 51484.375J

Hope this helps!