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
,
Answer:
The potential difference across the plates is 226 V.
Explanation:
Given;
area of the capacitor plate, A = 0.2 m²
separation, d = 0.1 mm = 0.1 x 10⁻³ m
charge on each plate, Q = 4 x 10⁻⁶ C
Charge on the capacitor is given by;
Q = CV
Where;
C is the capacitance of the capacitor, given as;
C = ε₀A / d
Then, the potential difference across the plates is given by;

Therefore, the potential difference across the plates is 226 V.
Explanation:
It is given that,
The acceleration of the toboggan, 
Initial speed of the toboggan, u = 0
We need to find the distance covered by the toboggan. Using the second equation of motion as :

At t = 1 s


At t = 2 s


At t = 3 s


Hence, this is the required solution.
To find the relative frequencies, divide each frequency by the total number of throws - in this case, 100.
Red: 10/100=1/10=0.1
Yellow:35/100=0.35
Blue:48/100= 0.48
Misses: 7/100=0.07
The event of landing in the red region has a relative frequency of 0.1 which means the dart landed in the red region about 10% (0.1 x 100%) of the time.