Answer:
exit velocity = 62 m/s
exit pressure is 98.52332 kPa
Explanation:
given data
pressure p1 = 80 kPa
temperature t1 = 27°C = 300 K
velocity v1 = 220 m/s
temperature t2 = 42°C = 315K
area exit = 370 cm²
lose heat at a rate = 18 kJ/s
gas constant of air = 0.287 kPa·m^3/kg·K.
h1 = 300.19 kJ/kg
h2 = 315.27 kJ/kg
to find out
exit velocity and exit pressure
solution
first we apply here energy balance equation to find out outlet velocity
Einlet = Eoutlet
m(h1 + v1²/2) = m (h2+v2²/2) +Q
m(v1²-v2²) /2 = m (h2 -h1) +Q
v2² = v1² - 2Cp Δt - 2Q/m
here Δt = h2 - h1 and put all value
v2² = 220² - 2(1.005)10³ (15) - 2(18)10³ /2.5
exit velocity = 62 m/s
so
now find outlet pressure that is
p2 = mRT / A2 v2
put value
p2 = 2.5 (287) 315 / (370 
62)
p2 = 98.52332 kPa
exit pressure is 98.52332 kPa
According to Newton`s law. Force exerted by car,
After adding an additional 400 kg of mass, the force will be same therefore the acceleration
Thus, the acceleration after adding the masses is 1.47 \ m/s^2.
Answer:
2.84 g's with the remaining 1 g coming from gravity (3.84 g's)
Explanation:
period of oscillation while waiting (T1) = 2.45 s
period of oscillation at liftoff (T2) = 1.25 s
period of a pendulum (T) =2π. 
where
- L = length
- a = acceleration
therefore the ration of the periods while on ground and at take off will be
=(2π 
) / (2π
)
where
- a1 = acceleration on ground while waiting
- a2 = acceleration during liftoff
= 
squaring both sides we have
= 
= 
assuming that the acceleration on ground a1 = 9.8 m/s^{2}
= 
a2 = 9.8 x
substituting the values of T1 and T2 into the above we have
a2 = 9.8 x 
a2 = 9.8 x 3.84
take note that 1 g = 9.8 m/s^{2} therefore the above becomes
a2 = 3.84 g's
Hence assuming the rock is still close to the ground during lift off, the acceleration of the rocket would be 2.84 g's with the remaining 1 g coming from gravity.
Answer:
300 Hz and 240 Hz
Explanation:
Beat frequency formed by the tuning fork is given by :
Here, the beat frequency, 
The frequency of a tuning fork, 
If 
If 
So, the tuning forks will give rise to a beat frequency are 240 Hz and 300 Hz. Hence, this is the required solution.
Very specific alignment of the Sun, Earth, and Moon. If the Moon is lined up precisely with the Sun from the Earth's point of view, the Moon will block Sunlight from reaching the Earth, causing a solar eclipse.
