Answer:
Net torque, 
Explanation:
It is given that,
Initial angular speed of the blade, 
Final angular speed of the blade, 
Time, t = 18 s
Radius of the disk, r = 0.13 m
Mass of the disk, m = 0.4 kg
We need to find the net torque applied to the blade. We know that in rotational mechanics the net torque acting on an object is equal to the product of moment of inertia and the angular acceleration such that,

The moment of inertia of the disk, 



Negative sign shows that the net torque is acting in the opposite direction of its motion. Hence, this is the required solution.
Answer:
distance- I think it is 6 then the displacement is 13.41
Explanation:
Answer:
EMF = 11.35 V
R = 0.031Ω
Explanation:
To find the battery's EMF and the internal resistance we need to use Ohm's law:

Where:
V: is the voltage
I: is the current
R is the resistance
We have:
The current through the battery is 64.2 A and the potential difference across the battery terminals is 9.36 V:
(1)
When only the car's lights are used, the current through the battery is 1.96 A and the terminal potential difference is 11.3 V:
(2)
By solving equation (1) and (2) for R we have:


Hence, the internal resistance is 0.031 Ω.
Now, by entering R into equation (1) we can find the battery's EMF:


Therefore, the battery's EMF is 11.35 V.
I hope it helps you!
<span>The answer to your question is choice: D</span>