Velocity of the sled is 3.2 m/s
It’s going to be both answer A and B but if you can only answer one then it’s going to be B
Answer:

Explanation:
Firstly, when you measure the voltage across the battery, you get the emf,
E = 13.0 V
In order to proceed we have to assume that the voltmeter offers no loading effect, which is a valid assumption since it has a very high resistance.
Secondly, the wires must be uniform. So the resistance per unit length is constant (say z). Now, even though the ammeter has very little resistance it cannot be ignored as it must be of comparable value/magnitude when compared to the wires. This is can seen in the two cases when currents were measured. Following Ohm's law and the resistance of a length of wire being proportional to it's length, we should have gotten half the current when measuring with the 40 m wire with respect to the 20 m wire (
). But this is not the case.
Let the resistance of the ammeter be r
Hence, using Ohm's law we get the following 2 equations:
.......(1)
......(2)
Substituting the value of r from (2) in (1), we have,

which simplifying gives us,
(which is our required solution)
putting the value of z in either (1) or (2) gives us, r = 0.5325 
If it takes cool air and passes it through the heat source using a fan or blower, the type of heat transfer is convection heat transfer.
<h3>What is heat transfer by convection?</h3>
Convection is the transfer of heat from one place to another due to the movement of fluid.
During heat transfer by convection, cold air replaces hot risen air.
Thus, if it takes cool air and passes it through the heat source using a fan or blower, the type of heat transfer is convection heat transfer.
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The sphere’s Electric potential energy is 1.6*
J
Given,
q=6. 5 µc, V=240 v,
We know that sphere’s Electric potential energy(E) = qV=6.5*
=1.6*
J
<h3>Electric potential energy</h3>
The configuration of a certain set of point charges within a given system is connected with the potential energy (measured in joules) known as electric potential energy, which is a product of conservative Coulomb forces. Two crucial factors—its inherent electric charge and its position in relation to other electrically charged objects—can determine whether an object has electric potential energy.
In systems with time-varying electric fields, the potential energy is referred to as "electric potential energy," but in systems with time-invariant electric fields, the potential energy is referred to as "electrostatic potential energy."
A tiny sphere carrying a charge of 6. 5 µc sits in an electric field, at a point where the electric potential is 240 v. what is the sphere’s potential energy?
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