Answer:
<em>The drop voltage is 0.3 V</em>
Explanation:
Electromotive Force EMF
When connecting a battery of internal resistance Ri and EMF ε to an external resistance Re, the current through the circuit is:

The battery has an internal resistance of Ro=2 Ω, ε=24 V and is connected to an external resistance of Re=158 Ω. Thus, the current is:


i = 0.15 A
The drop voltage is the voltage of the internal resistance:



The drop voltage is 0.3 V
Here in this case we can use work energy theorem
As per work energy theorem
Work done by all forces = Change in kinetic Energy of the object
Total kinetic energy of the solid sphere is ZERO initially as it is given at rest.
Final total kinetic energy is sum of rotational kinetic energy and translational kinetic energy

also we know that


Now kinetic energy is given by





Now by work energy theorem
Work done = 10500 - 0 = 10500 J
So in the above case work done on sphere is 10500 J
Answer:
B can take 0.64 sec for the longest nap .
Explanation:
Given that,
Total distance = 350 m
Acceleration of A = 1.6 m/s²
Distance = 30 m
Acceleration of B = 2.0 m/s²
We need to calculate the time for A
Using equation of motion

Put the value in the equation



We need to calculate the time for B
Using equation of motion
Put the value in the equation



We need to calculate the time for longest nap
Using formula for difference of time



Hence, B can take 0.64 sec for the longest nap .