1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
choli [55]
3 years ago
14

A rifle with a weight of 25 N fires a 4.5-g bullet with a speed of 240 m/s. (a) Find the recoil speed of the rifle. m/s (b) If a

650-N man holds the rifle firmly against his shoulder, find the recoil speed of the man and rifle.
Physics
1 answer:
asambeis [7]3 years ago
3 0

Answer:

The recoil speed of the man and rifle is v_{man}=0.016 ms^{-1}.

Explanation:

The expression for the force in terms of mg is as follows;

F=mg

Here, m is the mass and acceleration due to gravity.

Rearrange the expression for mass.

m=\frac{F}{g}

Calculate the combined mass of the man and rifle.

m_{man,rifle}=\frac{650+25}{g}

Put g=9.8 ms^{-2}.

m_{man,rifle}=\frac{650+25}{9.8}

m_{man,rifle}=68.88 kg

The expression for the conservation of momentum is as follows as;

m_{man}u_{man}+m_{bullet}u_{bullet}=m_{man}v_{man}+m_{rifle}v_{man,rifle}

Here, m_{man,rifle} is the mass of the man and rifle,  m_{rifle} is the mass of the rifle,u_{man},u{bullet}  are the initial velocities of the man and bullet and v_{man},v{man,rifle} are the final velocities of the man and rifle and rifle.

It is given in the problem that a rifle with a weight of 25 N fires a 4.5-g bullet with a speed of 240 m/s.

Convert mass of rifle from gram to kilogram.

m_{bullet}=4.5 g

m_{bullet}=.0045 kg

Put m_{bullet}=.0045 kg,m_{man,rifle}=68.88 kg , u_{man,rifle}=0, v_{bullet}= 240 ms^{-1} and u_{bullet}=0.

m_{man}(0)+m_{bullet}(0)=(68.88)v_{man,rifle}+(.0045)(240)

0=(68.88)v_{man,rifle}+(.0045)(240)

0=(68.88)v_{man,rifle}+1.08

(68.88)v_{man,rifle}=\frac{-1.08}{68.88}

v_{man,rifle}=-0.016 ms^{-1}  

Therefore, the recoil speed of the man and rifle is v_{man}=0.016 ms^{-1}.

You might be interested in
A film badge worn by a radiologist indicates that she has received an absorbed dose of 2. 5 x 10-6 gy. the mass of the radiologi
Anestetic [448]

Energy absorbed by the radiologist is 1.775*10^-6J.

To find the answer, we have to know about the radiation.

<h3>How much energy has she absorbed?</h3>
  • We have the expression for dose of absorption as,

           D=\frac{E}{m}

where; E is the energy absorbed and m is the mass of the body.

  • From the above expression, substituting appropriate values given in the question, we get,

         E=D*m=2.5*10^{-6}J/kg*71kg=1.775*10^{-4}J

Thus, we can conclude that, the Energy absorbed by the radiologist is 1.775*10^-6J.

<h3 />

Learn more about the radiation here:

brainly.com/question/24491547

#SPJ4

4 0
1 year ago
A ship travels with velocity given by 12, with current flowing in the direction given by 11 with respect to some co-ordinate axe
nataly862011 [7]

Answer:

v_x = 11.78 m/s

Explanation:

Velocity of the ship is given as

v = 12 units

the direction of the velocity of the ship is making an angle of 11 degree with the current

so we will have two components of the velocity

1) along the direction of the current

2) perpendicular to the direction of the current

so here we know that the component of the ship velocity along the direction of the current is given as

v_x = v cos\theta

v_x = 12 cos11

v_x = 11.78 m/s

7 0
2 years ago
Because atoms of elements in the same group of the periodic table have the same number of neutrons, they have similar properties
AURORKA [14]
False. What actually determines the properties of elements are the electrons, or aka valence electrons. They are used to bond, which determines its properties. 
4 0
3 years ago
Why are some substances dissolve both polar and nonpolar substances?
dlinn [17]

Answer:

Because water is polar and oil is nonpolar, their molecules are not attracted to each other.<em> polar solvents dissolve polar solutes, and nonpolar solvents dissolve nonpolar solutes.</em>

<em></em>

<em></em>

<em>please mark me as the brainliest :) </em>

<em></em>

<em>use your brain :)</em>

8 0
3 years ago
A ball has a mass of 0.046kg. Calculate the change in gravitational potential energy when the ball is lifted through a vertical
loris [4]

Answer:

PE=0.92414J and KE=0.28175J

Explanation:

Gravitational potential energy=mass*gravity*height

PE=mgh

Data,

M=0.046kg

H=2.05m

g=9.8m/s^2

PE=0.046kg * 9.8m/s^2 * 2.05m

PE =0.92414J

KE=1/2mv^2

M=0.046kg

V=3.5m/s

KE=[(0.046kg)*(3.5m/s)^2]\2

KE=0.28175J

3 0
2 years ago
Other questions:
  • 1. A container has a mass of 36 kg. How much does the container weigh?
    11·2 answers
  • Which form of energy is involved in weighing fruit on a spring scale?
    5·2 answers
  • What value must q2 have if the electric potential at point a is to be zero?
    15·1 answer
  • Which statement about the greenhouse effect is NOT true?.
    16·2 answers
  • One's perception depends on the way the brain interprets the stimuli. Please select the best answer from the choices provided T
    12·2 answers
  • A 1000-kg car is moving along a straight road down a 30∘30∘ slope at a constant speed of 20.0m/s20.0m/s. What is the net force a
    7·1 answer
  • The star nearest to our sun is Proxima Centauri, at a distance of 4.3 light-years from the sun. How far away, in km, is Proxima
    10·2 answers
  • A group of students wants to determine the internal resistance of a battery. They connect the battery to a variable resistor. Th
    15·1 answer
  • a car travels West 50km for 2 hours before heading south at a rate of 30 km per hour for 1.5 hours. What is the car's average sp
    9·1 answer
  • You want to calculate the area of your dorm
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!