contestada

A 0.050 kilogram bullet is fired from a 4.0 kilogram rifle which is initially at
rest. If the bullet leaves the rifle with a momentum of 20 kilogram-meters
per second, the rifle will recoil with a momentum of
(1) 1600 kg-m/s
(3) 20 kg-m/s
(2) 80 kg-m/s
(4) 0.25 kg-m/s

Respuesta :

skyluke89

The recoil momentum of the rifle is (3) 20 kg-m/s

Explanation:

We can solve this problem by using the law of conservation of momentum. In fact, the total momentum of the bullet-rifle system must be conserved before and after the shot, in absence of external forces.

Before the shot, the total momentum of the system is zero, since both the bullet and the rifle are at rest:

[tex]p=0[/tex] (1)

After the shot, the total momentum of the system is:

[tex]p=p_1 + p_2[/tex] (2)

where :

[tex]p_1 = 20 kg m/s[/tex] is the momentum of the bullet after the shot

[tex]p_2[/tex] is the recoil momentum of the rifle

Since momentum is conserved, (1) = (2):

[tex]0=p_1 + p_2[/tex]

Therefore we can find [tex]p_2[/tex]:

[tex]p_2 = -p_1 = -20 kg m/s[/tex]

where the negative sign tells that the direction is opposite to the momentum of the bullet.

Learn more about momentum:

brainly.com/question/7973509

brainly.com/question/6573742

brainly.com/question/2370982

brainly.com/question/9484203

#LearnwithBrainly

Otras preguntas