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
konstantin123 [22]
3 years ago
13

A 45-kg box is being pushed a distance of 6.4 m across the floor by a force P with arrow whose magnitude is 170 N. The force P w

ith arrow is parallel to the displacement of the box. The coefficient of kinetic friction is 0.22. Determine the work done on the box by each of the four forces that act on the box. Be sure to include the proper plus or minus sign for the work done by each force. (The floor is level and horizontal. Forces that act on the box: pushing force P, frictional force f, normal force N, and weight mg.)
Physics
1 answer:
Lapatulllka [165]3 years ago
6 0

Answer:

a) Work done on the box by pushing force P :  W= + 1088 J

b) Work done on the box  by the weight(W) of the box: W=0

c)  Work done on the box  by normal force N : W=0

d) Work done on the box  by the frictional force f  :W = -620.92 J

Explanation:

Work is defined as the Scalar product  of force F by the distance the body travels due to this force.  

W= F*d*cosα Formula ( 1)

Where:

W:  Work done on the body by the force (J)

d :  distance the body travels (m)

α : angle formed between force and displacement (°)

The work is positive (W+) if the force has the same direction of movement of the object.  (because α=0°, cos 0°=1)

The work is negative (W-) if the force has the opposite direction of the movement of the object.   (because α=180°, cos180°=-1)

The component of the force that performs work must be parallel to the displacement (because α=0°, cos 0°=1)

Perpendicular forces to displacement do not perform work (because α=90°,cos 90°=0)

Forces that act on the box:

Pushing force: P = 170 N          

Weight  :W=  m*g= 45 kg * 9.8 m/s²= 441 N

Normal force : N

Frictional force : f    

We apply Newton's second law to calculate N

∑F = m*a    Formula  (1)

∑F : algebraic sum of the forces in Newton (N)

m : mass in kilograms (kg)

a : acceleration in meters over second square (m/s²)

∑Fy = m*ay  ,   ay=0

N-W = 0

N=W = 441 N

We apply the following formula to calculate f:

f= μk*N  Formula (2)

Where:

Friction force : f

μk: coefficient of kinetic friction

N : Normal force (N)  

Data: μk= 0.22  ,  N= 441 N

We replace data in the formula (2)

f= 0.22*441

f= 97.02 N

Calculating the work done on the box by each of the four forces that act on the box

We apply the formula (1) to calculate the work

a) Work done on the box by pushing force P

P= 170 , d=6.4 m  , α= 0°

W=  P*d*cosα =  170N*6.4m*cos0°  = 1088 N *m

W=  1088 J

b) Work done on the box  by the weight(W) of the box

W= 441 N , d=6.4 m  , α= 90°

W= 441N *6.4m*cos90°=0

W=0

c)  Work done on the box  by normal force N

N= 441 N , d=6.4 m  , α= 90°

W= 441N *6.4m*cos90°=0

W=0

d) Work done on the box  by the frictional force f

f= 97.02 N , d=6.4 m  , α= 180°

W= 441N *6.4m*cos 180°

W = -620.92 N

You might be interested in
Which elements are metalloids
zhannawk [14.2K]

The six commonly recognised metalloids are boron, silicon, germanium, arsenic, antimony, and tellurium....

7 0
3 years ago
What do Oxygen and Fluorine do to do Copper?
Evgen [1.6K]
It corrodes the copper by oxydation
4 0
3 years ago
Dos cargas Q1=2pc y Q2=4pc estan separadas por una distancia de 6cm ¿con que fuerza se atraen?
noname [10]

Here we can use coulomb's law to find the force between two charges

As per coulombs law

]tex]F = \frac{kq_1q_2}{r^2}[/tex]

here we have

k = 9 * 10^9

q_1 = 2pC

q_2 = 4pC

r = 6cm = 0.06 m

now by using the above equation we have

F = \frac{9*10^9 * 2*10^{-12} * 4*10^{-12}}{0.06^2}

F = 2 * 10^{-11} N

so here the force between two charges is of above magnitude and this will be repulsive force between them as both charges are of same sign.

3 0
3 years ago
A boy weighs 40 kilograms. He runs at a velocity of 4 meters per second north. Which is his momentum?
Bogdan [553]
The boy's momentum is 160 kg*m/s north.

The formula of momentum is p = mv, where p is momentum.
p = 40 kg * 4m/s north
p =160 kg*m/s north

<span>Thank you for posting your question. I hope you found what you were after. Please feel free to ask me more.</span>


4 0
3 years ago
Read 2 more answers
The 1.53-kg uniform slender bar rotates freely about a horizontal axis through O. The system is released from rest when it is in
OlgaM077 [116]

Answer:

The spring constant = 104.82 N/m

The angular velocity of the bar when θ = 32° is 1.70 rad/s

Explanation:

From the diagram attached below; we use the conservation of energy to determine the spring constant by using to formula:

T_1+V_1=T_2+V_2

0+0 = \frac{1}{2} k \delta^2 - \frac{mg (a+b) sin \ \theta }{2}  \\ \\ k \delta^2 = mg (a+b) sin \ \theta \\ \\ k = \frac{mg(a+b) sin \ \theta }{\delta^2}

Also;

\delta = \sqrt{h^2 +a^2 +2ah sin \ \theta} - \sqrt{h^2 +a^2}

Thus;

k = \frac{mg(a+b) sin \ \theta }{( \sqrt{h^2 +a^2 +2ah sin \ \theta} - \sqrt{h^2 +a^2})^2}

where;

\delta = deflection in the spring

k = spring constant

b = remaining length in the rod

m = mass of the slender bar

g = acceleration due to gravity

k = \frac{(1.53*9.8)(0.6+0.2) sin \ 64 }{( \sqrt{0.6^2 +0.6^2 +2*0.6*0.6 sin \ 64} - \sqrt{0.6^2 +0.6^2})^2}

k = 104.82\ \  N/m

Thus; the spring constant = 104.82 N/m

b

The angular velocity can be calculated by also using the conservation of energy;

T_1+V_1 = T_3 +V_3  \\ \\ 0+0 = \frac{1}{2}I_o \omega_3^2+\frac{1}{2}k \delta^2 - \frac{mg(a+b)sin \theta }{2} \\ \\ \frac{1}{2} \frac{m(a+b)^2}{3}  \omega_3^2 +  \frac{1}{2} k \delta^2 - \frac{mg(a+b)sin \ \theta }{2} =0

\frac{m(a+b)^2}{3} \omega_3^2  + k(\sqrt{h^2+a^2+2ah sin \theta } - \sqrt{h^2+a^2})^2 - mg(a+b)sin \theta = 0

\frac{1.53(0.6+0.6)^2}{3} \omega_3^2  + 104.82(\sqrt{0.6^2+0.6^2+2(0.6*0.6) sin 32 } - \sqrt{0.6^2+0.6^2})^2 - (1.53*9.81)(0.6+0.2)sin \ 32 = 0

0.7344 \omega_3^2 = 2.128

\omega _3 = \sqrt{\frac{2.128}{0.7344} }

\omega _3 =1.70 \ rad/s

Thus, the angular velocity of the bar when θ = 32° is 1.70 rad/s

7 0
3 years ago
Other questions:
  • *13 POINTS* PLEASE HELP ASAP IM ON A TIME LIMIT ;-; WILL MARK BRAINLIEST what is the density of a sample that has a volume of 8c
    15·2 answers
  • If a wave has amplitude of 2 meters, a wavelength of 5 meters, and a frequency of 60 Hz, at what speed is it moving?
    13·2 answers
  • The rate an object is moving relative to a reference point is its
    5·1 answer
  • The wooden block is removed from the water bath and placed in an unknown liquid. In this liquid, only one-third of the wooden bl
    9·1 answer
  • Calculate the initial (from rest) acceleration of a proton in a 5.00 x 10^6 N/C electric field (such as created by a research Va
    13·1 answer
  • A man seeking to set a world record wants to tow a 101,000-kg airplane along a runway by pulling horizontally on a cable attache
    11·1 answer
  • A long, straight wire lies along the z-axis and carries a 4.20-A current in the +z-direction. Find the magnetic field (magnitude
    15·1 answer
  • What is the tensile strength of hair ?
    9·2 answers
  • What is the acceleration of an object that begins at 2 meters per second and after 5 minutes is travelling at 1 meter per second
    9·1 answer
  • 7. An Archimedean screw is a screw within a closely fitting cover, so that water can be raised when the
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!