Ask question

Ask question

All categories

3 years ago

6

The engine of a jet airplane pushes exhaust gases from burning fuel backward

1 answer:

olga nikolaevna [1]3 years ago

6 0

For more boost and to stop chases of fire

You might be interested in

A DJ starts up her phonograph player. The turntable accelerates uniformly from rest, and takes t1 = 11.9 seconds to get up to it

Degger [83]

Answer:

a) $\omega_1=8.168\,rad.s^{-1}$

b) $n_1=7.735 \,rev$

c) $\alpha_1 =0.6864\,rad.s^{-2}$

d) $\alpha_2=4.1454\,rad.s^{-2}$

e) $t_2=1.061\,s$

Explanation:

Given that:

initial speed of turntable, $N_0=0\,rpm\Rightarrow \omega_0=0\,rad.s^{-1}$

full speed of rotation, $N_1=78 \,rpm\Rightarrow \omega_1=\frac{78\times 2\pi}{60}=8.168\,rad.s^{-1}$

time taken to reach full speed from rest, $t_1=11.9\,s$

final speed after the change, $N_2=120\,rpm\Rightarrow \omega_2=\frac{120\times 2\pi}{60}=12.5664\,rad.s^{-1}$

no. of revolutions made to reach the new final speed, $n_2=11\,rev$

(a)

∵ 1 rev = 2π radians

∴ angular speed ω:

$\omega=\frac{2\pi.N}{60}\, rad.s^{-1}$

where N = angular speed in rpm.

putting the respective values from case 1 we've

$\omega_1=\frac{2\pi\times 78}{60}\, rad.s^{-1}$

$\omega_1=8.168\,rad.s^{-1}$

(c)

using the equation of motion:

$\omega_1=\omega_0+\alpha . t_1$

here α is the angular acceleration

$78=0+\alpha_1\times 11.9$

$\alpha_1 = \frac{8.168 }{11.9}$

$\alpha_1 =0.6864\,rad.s^{-2}$

(b)

using the equation of motion:

$\omega_1\,^2=\omega_0\,^2+2.\alpha_1 .n_1$

$8.168^2=0^2+2\times 0.6864\times n_1$

$n_1=48.6003\,rad$

$n_1=\frac{48.6003}{2\pi}$

$n_1=7.735\, rev$

(d)

using equation of motion:

$\omega_2\,^2=\omega_1\,^2+2.\alpha_2 .n_2$

$12.5664^2=8.168^2+2\alpha_2\times 11$

$\alpha_2=4.1454\,rad.s^{-2}$

(e)

using the equation of motion:

$\omega_2=\omega_1+\alpha_2 . t_2$

$12.5664=8.168+4.1454\times t_2$

$t_2=1.061\,s$

4 0

3 years ago

Which of the following is a noncontact force? A. electrical forces B. gravitational forces C. magnetic forces D. all of these

goblinko [34]

D. all of these

hope this helps.

6 0

3 years ago

Read 2 more answers

It takes 9 sec for a 10 newton force to move an object 4 meters to the right. What is direction & magnitude of the force

lana66690 [7]

Answer:

the question is wrong

Explanation:

M is not given
after 9 second the acceleration multiply by the time divided by two then multiplied by the time is equal to 4 meter
((10/Mm/s *9s-)

3 0

3 years ago

How long will it take for a car to accelerate to come to a stop if it is traveling at 20m/s and the car has a maximum decelerati

Pachacha [2.7K]

When the car comes to a stop, the final velocity must be 0 m/s.
Since the car js decelerating in a forward direction, acceleration must be negative.

final v = initial v + a•t
0 = 20 + (-6)t
t = 3.33s

5 0

3 years ago

A sound wave is produced when a medium begins to blank .

faust18 [17]

The answer is vibrate

5 0

3 years ago

Read 2 more answers