Hello!
Since the two weights are <em>off</em> the table, the block will move towards letter F.
I hope this helps :))
Answer:

the answer is A.
Explanation:
Using the laws of newton:
∑F = ma
where ∑F is the sumatory of forces acting in the system, m the mass and a the acelertion of the system.
Then, if the block is moving with constant velocity, its aceleration is equal to 0, so:
∑F = m(0)
∑F = 0
It means that:
F -
= 0
where F is the force applied and
is the friction force. Replacing the value of F, we get:
310N -
= 0
Finally, solving for
:

The correct field line would be A.
Ideal gas law:
PV = nRT
P = pressure, V = volume, n = # of moles, R = gas constant, T = temperature
Equipartition theorem:
Each degree of freedom that a molecule has adds 0.5kT to its total internal energy where k = Boltzmann's constant and T = temperature
2nd law of thermodynamics:
A set of governing principles that restrict the direction of net heat flow (always hot to cold, heat engines are never 100% efficient, entropy always tends to increase, etc)
Clearly the answer is Choice A