XA 2 2.1.4 Quiz: First Law of Thermodynamics
Question 2 of 10
2 Points
Which of the following situations would cause the greatest increase in the
motion of molecules in a system?
A. Q = +50 J, W = -50 J
O B. Q = +50 J, W = +50 J
O c. Q = -50 J, W = -50 J
O D. Q = -50 J, W = +50 J

A.

Q = +50 J, W = -50 J

Explanation:

According to first law of thermodynamics, which can be expressed as;

dU = Q - W

Where

dU = change in internal energy

Q = added heat

W = work done by the system

If W is positive, work is done on the system. And if Q is negative, the system loses heat to the surrounding.

In the question above, the situation that would cause the greatest increase in the motion of molecules in a system will be option A

Q = +50 J, W = -50 J

Since the system gained heat and work is been done by the system.

d₁ = displacement of tern from arctic to antarctic = 11000 miles

d₂ = displacement of tern from antarctic to arctic =   - 11000 miles

d = total displacement for the journey

total displacement for the journey is given as

d = d₁ + d₂

d = 11000 + (-11000)

d = 0 miles

t₁ = time of travel from arctic to antarctic = 3 months = 3 x 30 days = 90 days

t₂ = time of travel from antarctic to arctic = 3 months = 3 x 30 days = 90 days

t = total time of travel

total time of travel is given as

t = t₁ + t₂

t = 90 + 90

t = 180 days

average velocity is given as

average velocity = total displacement/ total time

v = d/t

v = 0/180

v = 0 miles/day

the order for strong to weak forces such as

strong nuclear force → electromegnetic force → weak nuclear force → gravitational force

the fundamental forces are those forces that act between to objects or element to make interactions. there are four types of fundamental forces such as strong and weak nuclear forces (due to protons and electrons), electromagnetic force (due to the motion of electrons) and gravitational force (due to orbital movement of the planet). if these forces are arranged on the basis of their maximum strength then the order is

strong nuclear force → electromegnetic force → weak nuclear force → gravitational force