Answer:
B. QC > 0; QH < 0
Explanation:
Given that there are two reservoir of energy.
Sign convention for heat and work :
1.If the heat is adding to the system then it is taken as positive and if heat is going out from the system then it is taken as negative.
2. If the work is done on the system then it is taken as negative and if the work is done by the system then it is taken as positive.
From hot reservoir heat is going out that is why it is taken as negative
From cold reservoir heat is coming inside the reservoir that is why it is taken as positive
That is why the answer will be
,
The answer is 35 degrees Celsius. Hope I helped :) Please vote brainliest.
Answer:
Torque decreases .
Explanation:
The tape is pulled at constant speed , speed v is constant , so there is
v = ω r where ω is angular speed and r is radius , As radius decreases , angular speed ω increases , So there is angular acceleration .
Let it be α . Let I be moment of inertia of reel .
Reel is in the form of disc
I = 1/2 m r²
I x α = torque
1/2 m r² x α = torque
As the reel is untapped , its mass decreases , r also decreases , so torques also decreases .
Answer:
Science can only answer inquiries about effects and events that are discovered, defined, and studied in the material realm. It cannot answer questions about the one basic cause of all effects and events.
4m/s due north of the store
Explanation:
Given parameters:
Time taken = 45s
Displacement = 180m
Unknown
Velocity = ?
Solution:
Velocity is the displacement of a body per unit time. Velocity is a vector quantity that has both magnitude and direction.
Velocity = 
= 
Velocity = 4m/s due north of the store
Learn more:
Velocity brainly.com/question/10883914
#learnwithBrainly
