The area of the sprinkles can be determined through the area of a circle that is pi * r^2 in which the given dimensions above are the radii, r. The second scenarios radius is only half of the original, that is 4 ft. In this case, we can compute the area of the second again. We calculate next the difference of two areas of circles.
Answer:

Explanation:
given data
Radius of sphere 3.0 cm
charge Q = 2.0 m C
We know that maximum electric field is given as

electric field inside the sphere can be determine by using below relation



Answer:
Da=(1/4)Db
Explanation:
t = Time taken
u = Initial velocity
v = Final velocity
s = Displacement
a = Acceleration due to gravity = 9.81 m/s²
When s = Da, t = t

When s = Db, t = 2t

Dividing the two equations

Hence, Da=(1/4)Db
To make the motor turn faster we can:
(a) increase the current
(b) use stronger magnets
(c) push the magnets closer to the coil
(d) put an iron centre piece into the coil
(e) adding more sets of coils
The thermal energy is where the work of friction comes from. That is what stops it eventually. In this case a counter force of 10N is applied over the distance of 30.0m. The energy is given by Force*Distance. Here this is 300J. This friction work is the thermal energy.