<span>The oven will transform electrical energy into heat energy</span>
Answer:
50km/h
Explanation:
Average velocity = change in distance (or distance travelled) divided by/ the change in time (or time taken.)
The change in distance has been given as 100km.
The change in time is 3pm-1pm = 2 hours.
Therefore the average velocity was 100/2 = 50km/h (to the east).
Hope this helped!
-- During the time the ball is flying from the high roof to the low roof,
it's going to fall (100-25) = 75 meters.
How long does it take an object dropped from rest to fall 75 meters ?
Distance = (1/2) · (gravity) · (time)²
75 m = (4.9 m/s²) · (time)²
Time² = (75 m) / (4.9 m/s²)
Time² = 15.31 sec²
Time = √(15.31 sec²) = 3.91 seconds
So the ball has to cover the horizontal distance of 20 meters
in 3.91 seconds.
Distance = (speed) · (time)
20 m = (speed) · (3.91 sec)
Speed = (20 m) / (3.91 sec)
Speed = 5.11 m/s
Answer:
(a) 
(b) 
: From the air to the surroundings.
Explanation:
Hello,
(a) In this case, we can compute the area at the entrance by firstly computing the inlet volumetric flow:
Then, with the velocity, we compute the area:
(b) In this case, via the following energy balance for the nozzle:
We can easily compute the change in the enthalpy by using the given Cp and neglecting the work (no done work):
Finally, the heat turns out:
![Q=-348.795kW+\frac{1}{2}*2.3\frac{kg}{s}*[(460\frac{m}{s})^2 -(3\frac{m}{s})^2 ]\\\\Q=-348.795kW+243329.65W*\frac{1kW}{1000W}\\ \\Q=-105.5kW](https://tex.z-dn.net/?f=Q%3D-348.795kW%2B%5Cfrac%7B1%7D%7B2%7D%2A2.3%5Cfrac%7Bkg%7D%7Bs%7D%2A%5B%28460%5Cfrac%7Bm%7D%7Bs%7D%29%5E2%20%20%20-%283%5Cfrac%7Bm%7D%7Bs%7D%29%5E2%20%20%5D%5C%5C%5C%5CQ%3D-348.795kW%2B243329.65W%2A%5Cfrac%7B1kW%7D%7B1000W%7D%5C%5C%20%5C%5CQ%3D-105.5kW)
Such sign, means the heat is being transferred from the air to the surroundings.
Regards.
Here it is the use of vector and conservation of momentum !
so,
√(16^2+21^2) ×1000= 3000 v
v =8.8 m/s
so answer is B !
if you have any doubt, you can ask ! just comment !
