Answer:
A
Explanation:
<em>The gold used in the making of jewelry is usually not pure but a heterogeneous mixture of metals. Pure gold is quite soft and even though it may look better in appearance compared to those made using heterogeneous mixtures, it usually bends easily. Hence, in order to make the jewelry more durable, gold is usually mixed with other metals to form a heterogeneous mixture. </em>
The correct option is A.
Answer:
a) 2.85 kW
b) $ 432
c) $ 76.95
Explanation:
Average price of electricity = 1 $/40 MJ
Q = 20 kW
Heat energy production = 20.0 KJ/s
Coefficient of performance, K = 7
also
K=(QH)/Win
Now,
Coefficient of Performance, K = (QH)/Win = (QH)/P(in) = 20/P(in) = 7
where
P(in) is the input power
Thus,
P(in) = 20/7 = 2.85 kW
b) Cost = Energy consumed × charges
Cost = ($1/40000kWh) × (16kW × 300 × 3600s)
cost = $ 432
c) cost = (1$/40000kWh) × (2.85 kW × 200 × 3600s) = $76.95
Answer:
An arrow represents displacement. Because it's a vector quantity.
Vector quantity= Direction+Magnitude
When an arrow is put above a unit like
it means that it's a vector quantity.
Hope this helps ;) ❤❤❤
The working equation would be Vf (final velocity) = Vi
(initial velocity) + a (acceleration) t (time). The given data are the initial
velocity (5.0 m/s), acceleration (-2.5 m/s^2, negative since it is said to
decelerate) and the final velocity (0 m/s, since it will put to a stop). The
time would be 2 seconds.
