I posted this because I got it correct. The answer is 28J.
Answer:
2280 V
Explanation:
distance between the plates, d = 4 cm = 0.04 m
Electric field strength, E = 5.7 x 10^4 V/m
The formula for potential difference is given by
V = E x d
V = 5.7 x 10^4 x 0.04
V = 2280 V
thus, the potential difference between the plates is 2280 V.
Coefficient of performance or more commonly known as COP is calculated through the equation,
COP = ((T₂)/(T₂ - T₁))
where T₂ is the hot temperature and T₁ is the cold temperature. Similarly, these can also be,
COP = heat ejected / (heat ejected - heat provided)
Substituting,
COP = 22,000 / (22,000 - 15,000) = 3.14
Thus, the value of the COP is approximately 3.14.
The answer is a. endothermic.
In endothermic reaction, as the name suggests, the reactants require energy absorption to form and complete the chemical reaction to form products.
And even if you don't know the answer, you can exclude all other answers by scientific logic and you will be left with the correct answer.
Hope this helps.
Answer:
b) 0.5 m/s
Explanation:
let V be the averare speed of the object.
the average speed is given by:
V = total distance / total time
= (20+20)/(30+50)
= 0.5 m/s
Therefore, the average speed of the object is 0.5 m/s.