Answer:
93.75 m/s
Explanation:
Given:
The frequency of the sound = 750 Hz
The number of pistons making the sound = 8
Revolutions made by the engine = 2000 revolutions/ km
Thus,
the frequency of sound by 1 piston = 750 / 8 = 93.75 Hz
also, it is given that for every other revolution sound is made.
thus, for every 2 revolution sound is made
therefore,
Number of revolutions per second = 93.75 Hz × 2 = 187.5 rev/s
Now,
the speed of the car will be calculated as:
= Number of revolutions per second / Revolutions made by the engine
or
The speed of the car = 
or
The speed of the car = 0.09375 km/s = 93.75 m/s
Answer:magnitude -5; angle 160°
Explanation:
Vector A is described as having magnitude 5 and angle -20°.
To get an equivalent vector, we either leave the magnitude at 5 and add 360° to the angle, or we reverse the magnitude to -5 and add 180° to the angle.
5 @ -20° = 5 @ 340°
5 @ -20° = -5 @ 160°
The third one is the answer.
The formula for gravitational potential energy is Ep= mgh. Lets convert 594 km into m: 594 x 1,000 = 594,000 m. So we do: Ep= (1,800kg)(9.8N/kg)(594,000m) = (17,640N)(594,000) = 10,478,160,000 J.
M° = 2.5 kg/sec
For saturated steam tables
at p₁ = 125Kpa
hg = h₁ = 2685.2 KJ/kg
SQ = s₁ = 7.2847 KJ/kg-k
for isotopic compression
S₁ = S₂ = 7.2847 KJ/kg-k
at 700Kpa steam with S = 7.2847
h₂ 3051.3 KJ/kg
Compressor efficiency
h = 0.78
0.78 = h₂ - h₁/h₂-h₁
0.78 = h₂-h₁ → 0.78 = 3051.3 - 2685.2/h₂ - 2685.2
h₂ = 3154.6KJ/kg
at 700Kpa with 3154.6 KJ/kg
enthalpy gives
entropy S₂ = 7.4586 KJ/kg-k
Work = m(h₂ - h₁) = 2.5(3154.6 - 2685.2
W = 1173.5KW
THe answer will be C
because if you put somethin ht next to something cold it will become cooler and if you be two things that are hot next to each other they will remain hot.