A 1500-kg car travelling 90 km/h[N] collides with a 1200-kg minivan travelling 40 km/h[S]. After the collision, the two vehicles stick together.

a. Calculate the initial momentum of the car and the minivan.

b. Using the law of conservation of momentum, determine the total momentum of the two vehicles after the collision.

c. Calculate the final velocity of the two vehicles after the collision in metres per second.

Answers

Answer 1

Answer:

A) car - 37500 kg*m/s, minivan - 13332 kg*m/s

B) 50832 kg*m/s

C) 18.83 m/s

Explanation:

Realize that sticky collisions are modeled by: m1v1+m2v2=(m1+m2) vf

conevert to m/s....car going 25 m/s, minivan going 11.11 m/s

A) p=mv

p(car)=(1500)(25)

p(car)=37500 kg*m/s

p(minivan)=(1200)(11.11)

p(minivan)=13332 kg*m/s

B) 37500+13332=50832 kg*m/s

C) 37500+13332=(1500+1200) vf

50832=2700(vf)

18.83 m/s = vf


Related Questions

Do blood cells have a nuclei? Describe the shape of blood platelets.

Answers

Answer: Mature red blood cells don't have nuclei.

Explanation: " Platelets are irregularly shaped, have no nucleus, and typically measure only 2–3 micrometers in diameter. "

Hope this Helps!!

please answer asap! will give brainliest if correct! ^^

A train of waves is moving at a speed of 30 m/s. The frequency of the waves is 10 Hz. What is the wavelength?
a. 300 m
b. 30 m
c. 3 m
d. 0.1 m

Answers

Answer:

the answer is c, 3m......

When a train is moving at the speed of 30 m/s. The wavelength of the wave is 3 m.

What is wavelength?

Wavelength is the characteristic of the wave which represents the distance between the adjacent crest or trough of the wave.

Given is the speed of the train of waves 30 m/s and frequency of the wave is 10 Hz, then the wavelength is related to speed and wavelength as

v = fλ

30 = 10 × λ

λ = 3 m

Thus, the wavelength of the wave is 3 m.

Learn more about wavelength.

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What is happening in the graph shown below?


A.
The object moves away from the origin at a speed of 3 m/s, stands still 6 m away from the origin for 3 seconds, then moves toward the origin at a speed of 2 m/s.
B.
The object moves toward the origin at a speed of 3 m/s, stands still 6 m away from the origin for 3 seconds, then moves away from the origin at a speed of 2 m/s.
C.
The object moves toward the origin at a speed of 6 m/s, stands still 6 m away from the origin for 3 seconds, then moves away from the origin at a speed of 8 m/s.
D.
The object moves away from the origin at a speed of 6 m/s, stands still 6 m away from the origin for 3 seconds, then moves toward the origin at a speed of 8 m/s.

Answers

Answer:

D. The object moves away from the origin at a speed of 3 m/s, stands still 6 m away from the origin for 3 seconds, then moves toward the origin at a speed of 2 m/s.

Explanation:

I just got it right lol

Which of the following types of mirrors has an optical axis?
a convex mirror
a concave mirror
a double convex mirror
All of the choices are correct.

Answers

Answer:

its B

Explanation:

someone please help I can mark brainless

Answers

The answer here is B I hope that helps you if not I’m really sorry

Q1what is pinhole camera?​

Answers

A pinhole camera is a simple camera without a lens but with a tiny aperture (the so-called pinhole)—effectively a light-proof box with a small hole in one side. Light from a scene passes through the aperture and projects an inverted image on the opposite side of the box, which is known as the camera obscura effect.

A reaction occurs when a compound breaks down. This reaction has one reactant and two or more products. Energy, as from a battery, is usually needed to break the compound apart.

Answers

Answer:

decomposition

Explanation:

A block is sliding along a horizontal surface with 100 J of kinetic energy. The kinetic frictional force stops the block in 5 seconds.

What is the rate (in J/s) at which the force of kinetic friction does work?

Answers

Answer:

20 J/s

Explanation:

Given data

Kinetic energy=100 J

Time= 5 seconds

Hence the rate at which the kinetic friction work is

=100/5

=20 J/s

Therefore the answer is 20 J/s

Which of the following is true for the entropy of the universe?
A It is always decreasing.
B It is always increasing.
C It is always negative.
D It is always a constant.

Answers

Answer:

B It is always increasing.

Explanation:

In Physics, entropy can be defined as the tendency or ability of a substance to reach maximum disorder i.e to be randomly distributed.

This ultimately implies that, entropy is a thermodynamic quantity that measures the degree of maximum disorder or randomness of a system.

The S.I unit used for the measurement of the degree of maximum order or randomness of a system is Joules per Kelvin (JK¯¹). An example of entropy is the mixing of ideal gases.

Generally, the entropy in an irreversible process always increases and as such the change in entropy has a positive value.

Hence, the entropy of the universe is always increasing because its energy flow is considered to be in a downward direction rather than upward i.e from a hot region to a cold region; making the energy to be evenly distributed.

the region where a magnet force is strongest is at the​

Answers

Answer:

Magnetic poles

Explanation:

Magnetic poles are the regions where the magnet's force is strongest, one is the north pole and one is the south pole.

The region were there are the strongest magnetic felts are in the North Pole and South Pole

When grip strength increases:

a. action potential voltage increases.
b. action potential frequency decreases.
c. action potential frequency increases.
d. action potential frequency increases.
e. the number of active motor units increases.

Answers

Answer:

e. the number of active motor units increases.

Explanation:

There is a direct relationship between the number of active motor units and the grip strength in a given scenario. For example, increase in the grip strength leads to increase in the number of active motor units. In the other-hand, the decrease in grip strength leads to the decrease in the number of active motor units.

A motorist is driving at 15 m/s when she sees that a traffic light 315m ahead has just turned red. She knows that this light stay red for 25 s, and she wants to be 20 m from the ligt when it turns green again. Taht way, she will still be able to stop if the light stays red longer than expected. She applies the brake gradually such that her acceleration is ax(t)= c + bt, where c and b are constant. Assume she starts with a constant speed at the origin.

Find the values of c a b and any other unknown constants in order to answer the following questions.

1. Given the motorist's acceleration as a function of time, what are her position and velocity fucntions? - Do not use numbers for any constant here. Only derive the position and velocity functions.

2. What is her speed as she reaches the light?

Answers

Answer:

1)   x = x₀ + vot - ½ c t² - 1/6 bt³,    v = v₀ - ct - ½ b t²

2)   v₁ = 5.25 m/s,         v₂ = -8 m/s

Explanation:

1) For this exercise, the relationship of the body is not constant, so you must use the definition of speed and position to find them.

acceleration is

           a = c + bt

a) the relationship between velocity and acceleration

           a = [tex]\frac{dv}{dt}[/tex]

           dv = -a dt

The negative sign is because the acceleration is contrary to the speed to stop the vehicle.

we integrate

           ∫ dv = - ∫ a dt

           ∫ dv = -∫ (c + bt) dt

            v = -c t - ½ b t²

This must be valued from the lower limit, the velocity is vo, up to the upper limit, the velocity is v for time t

             v - v₀ = -c (t-0) - ½ b (t²-0)

             v = v₀ - ct - ½ b t²

b) the velocity of the body is

             v = [tex]\frac{dx}{dt}[/tex]

             dx = v dt

we replace and integrate

              ∫ dx = ∫ (v₀ - c t - ½ bt²) dt

              x-x₀ = v₀ t - ½ c t² - ½ b ⅓ t³

Evaluations from the lower limit the body is at x₀ for t = 0 and the upper limit the body is x = x for t = t

           x - x₀ = v₀ (t-0) - ½ c (t²-0) + [tex]\frac{1}{6}[/tex]  (t³ -0)

 

           x = x₀ + vot - ½ c t² - 1/6 bt³

2) The speed when you reach the traffic light

Let's write the data that indicates, the initial velocity is vo = 15 m / s, the initial position is xo = 315m, let's use the initial values ​​to find the constants.

       t = 25 s x = 20

we substitute

          20 = 315 + 15 25 - ½ c 25² - 1/6 b 25³

         0 = 295 + 375 - 312.5 c - 2604.16 b

         670 = 312.5 c + 2604.16 b

we simplify

         2.144 = c + 8.33 b

Now let's use the equation for velocity,

        v = v₀ - ct - ½ b t²

        v = 15 - c 25 - ½ b 25²

        v = 15 - 25 c - 312.5 b

               

let's write our two equations

        2.144 = c + 8.33 b

        v = 15 - 25 c - 312.5 b

Let's examine our equations, we have two equations and three unknowns (b, c, v) for which the system cannot be solved without another equation, in the statement it is not clear, but the most common condition is that if the semaphore does not change, it follows with this acceleration (constant) to a stop

               a = c + b 25

from the first equation

              c = 8.33 / 2.144 b

              C = 3.885 b

we substitute in the other two

            v = 15 - 25 (3.885 b) - 312.5 b

            v = 15 - 409.6 b

final acelearation

            a = 28.885 b

           

let's use the cinematic equation

               [tex]v_{f}^2[/tex]= v² - 2 a x

                0 = v² - 2a 20

               0 = v² - (28.885b) 40

               v² = 1155.4 b

we write the system of equations

               v = 15 - 409.6 b

               v² = 1155.4 b

resolve

              v²= 1155.4 ( [tex]\frac{15 -v }{409.6}[/tex] )

              v² = 2.8 ( 15 -v)

              v² + 2.8 v - 42.3 = 0

              v=  [ -2.8 ±[tex]\sqrt {2.8^2 + 4 \ 42.3) }[/tex] ]/2 = [-2.8 ± 13.3]/2

              v₁ = 5.25 m/s

              v₂ = -8 m/s

A 64.0-kg person holding two 0.900-kg bricks stands on a 2.00-kg skateboard. Initially, the skateboard and the person are at rest. The person now throws the two bricks at the same time so that their speed relative to the person is 19.0 m/s. What is the recoil speed of the person and the skateboard relative to the ground, assuming the skateboard moves without friction?

Answers

Answer:

0.518 m/s

Explanation:

To solve this question, we would use the Law of conservation of momentum.

It is stated that the skateboard and the person were at rest initially, this means that their initial momentum is 0. Since they aren't moving.

And from the law if conservation of momentum, we know that initial momentum must be equal to final momentum.

The final momentum of the bricks will be 2* 0.9 * 19 = 34.2 kg m/s.

This means that the momentum of the person and that of the skateboard has to be 34.2 kg m/s also, although, it will be in the opposite direction.

Mass of the person plus that of the skateboard is

64 + 2 = 66 kg,

If we divide the momentum of the person and that of the skateboard by the mass of the both of them, we get the speed at which they are moving after the bricks are thrown

Recoil speed = (34.2 kg m/s)/(66 kg) = 0.518 m/s.

The recoil speed of the person is 0.518 m/s

Calculation of the recoil speed of the person:

As per the conservation of momentum, the initial momentum should be equivalent to the final momentum

So, here the final momentum should be

=  2* 0.9 * 19

= 34.2 kg m/s.

Now the mass of the person should be

= 64 + 2

= 66 kg,

Now the recoil speed should be

Recoil speed = (34.2 kg m/s)/(66 kg)

= 0.518 m/s.

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What are some possible factors that can be the X
and Y axis of a motion graph?

Answers

Answer:

x-Speed/velocity

y-time.

Explanation:

because Speed is a rate of change of distance while time how long it takes a a car to move to a specific point

help me pls
An object accelerates if it:

a.) changes the direction of its velocity but not the magnitude

b.)changes the magnitude of the velocity but not the direction

c.)changes its speed

d.) all of the above

e.) none of the above

Answers

Answer:

D

Explanation:

Select the correct answer.
Why are the requirements to become a congressional representative and a senator different?
A.
The framers didn’t want senators to worry about their constituents as often as representatives do.
B.
The framers gave senators more lawmaking powers and responsibilities than representatives.
C.
The framers wanted senators to be more mature and more experienced than representatives.
D.
The framers thought senators and representatives should have reasons to argue with each other.

Answers

The framers wanted senators to be more mature and more experienced than representatives. (C)

Answer:

C -> The framers wanted senators to be more mature and more experienced than representatives.

which one is odd copper,plastic,rubber​

Answers

Answer:

It's plastic.

trust me it's plastic, i've rad it somewhere.

All of them have something that's not like the others.

-- Rubber is the only one on the list that has two repeated letters.

-- Plastic is the only one on the list thagt has no repeated letters.

-- Plastic is the only one on the list that has no 'r' in its name.

-- Copper is the only one on the list that is an element, not a compound.

-- Copper is the only good electrical conductor on the list.

-- Plastic is the only one on the list with more than six letters in its name.

-- Rubber is the only one on the list with no 'p' in its name.

-- Plastic is the only one on the list that doesn't end in "-er".

Use the drop-down menus to complete each statement about tornado safety.

Before a tornado warning occurs, you should
✔ have a disaster plan ready.

If you’re indoors during a tornado, you should
✔ go to the basement.

If you’re outdoors during a tornado, you should
✔ lie in a ditch or low-lying area.

Answers

Are you telling us the answer

Answer:

correct tysmm

Explanation:

(a) What do you mean by rest?​

Answers

It’s where the vehicle stops moving.

I hope this helps.

A motorcycle is traveling along a highway at 29 m/s. How far does the motorcycle travel in 18 s?

Answers

Answer:

the motorcycle travels 522 miles in 18 seconds Explanation: 29 x 18 is 522 I'm pretty sure that's what it was asking but I don't know

Even in the most advanced circuits, we cannot oscillate electrons back and forth at that rate through wires. But we can oscillate charges back and forth quickly enough to broadcast TV using radio wave signals. At what frequency do the electronics at the TV station need to have the charges oscillate back and forth on a TV broadcast antenna to transmit a typical TV signal (say a radio wave transmission signal with a wavelength of 1 meter)

Answers

Answer:

the oscillations of the electrons must be in the 10⁸ Hz = 100 MHz range

Explanation:

The speed of a wave of radio, television, light, heat, all are manifestations of electromagnetic waves that are oscillations of electric and magnetic fields that support each other, the speed of all these waves is the same and the vacuum is equal to c = 3 108 m / s

All waves have a relationship between the speed of the wave, its frequency and wavelength

          c = λ f

          f = c /λ

for this case lam = 1 m

          f = 3 10⁸/1

          f = 3 10⁸ Hz

the oscillations of the electrons must be in the MHz range

It should be clarified that the speed of light in air is a little lower

          n = c / v

          v = c / n

the refractive index of vacuum is n = 1 and the refractive index of air is n = 1.000002

(will give brainliest to whoever answers first and explains reasoning) A 10kg object is spun around in a circle with a centripetal acceleration of 3.5m/s^2. What is the centripetal force acting on the object?

Answers

Answer:

35 N

Explanation:

F = ma

centripetal force = 10(3.5) = 35 N

Linearly polarized light whose Jones vector is [0 1] (horizontally polarized) is sent through a train of two linear polarizers. The first is oriented with its transmission axis at 45 degrees and the second has its transmission axis vertical. Show that the emerging light is linearly polarized in the vertical direction; that is, the plane of polarization has been rotated by 90 degrees.

Answers

Answer:

Following are the solution to the given question:

Explanation:

The input linear polarisation was shown at an angle of [tex]2 \mu[/tex]. It's a very popular use of a half-wave plate. In particular, consider the case [tex]\mu = 45 \pm[/tex], at which the angle of rotation is [tex]90\pm[/tex]. HWP thereby provides a great way to turn, for instance, a linear polarised light that swings horizontally to polarise vertically. Illustration of action on event circularly polarized light of the half-wave platform. Customarily it is the slow axis of HWP that corresponds to either the rotation. Note that perhaps the vector of polarization is "double-headed," i.e., the electromagnetic current swinging back and forward in time. Therefore the turning angle could be referred to as the rapid axis to reach the same result. Please find the attached file.

A hook in boxing primarily involves horizontal flexion of the shoulder while maintaining a constant angle at the elbow. During this punch, the horizontal flexor muscles of the shoulder contract and shorten at an average speed of 75 cm/s. They move through an arc length of 5 cm during the hook, while the fist moves through an arc length of 100 cm. What is the average speed of the fist during the hook

Answers

Answer:

average speed of the fist during the hook = 15 m/s or 1500 cm/s

Explanation:

We are given;

Speed of shoulder contraction, v_s = 75 cm/s = 0.75 m/s

Distance moved through the arc length by shoulder, d_s = 5 cm = 0.05 m

Distance moved by the fist, d_f = 100 cm = 1 m

Now, we are to find the average speed of the fist during the hook; v_f

Thus can be gotten from proportion;.

d_f/d_s = v_f/ v_s

Making V_f the subject, we have;

v_f = (d_f × v_s)/d_s

Thus;

v_f = (1 × 0.75)/0.05

v_f = 0.75/0.05

v_f = 15 m/s

__________ and __________ both heavily relied on dream analysis in their treatment of patients. A. Alfred Adler . . . Albert Ellis B. Alfred Adler . . . Carl Jung C. Sigmund Freud . . . Carl Jung D. Sigmund Freud . . . Alfred Adler

Answers

Answer:

C. Sigmund Freud . . . Carl Jung

Explanation:

edge 2021

C.Sigmund Freud and Carl Jung both heavily relied on dream analysis in their treatment of patients.

What is Freud most famous for?

Freud is well-known for inventing and developing the approach of psychoanalysis; for articulating the psychoanalytic idea of motivation, intellectual infection, and the structure of the unconscious; and for influencing medical and popular conceptions of human nature by using positing both everyday and strange thought.

Sigmund Freud was an Austrian neurologist who's perhaps maximum known as the founding father of psychoanalysis. Freud advanced a fixed of therapeutic strategies centered on communication therapy that worried the use of techniques that include transference, loose affiliation, and dream interpretation.

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1. When an unbalanced force acts on an object,
O the object remains at rest
the weight of the object decreases.
O the object's motion changes.
the inertia of the object increases.

Answers

The object’s motion changes :)

A 10.0-g bullet is fired into, and embeds itself in, a 1.95-kg block attached to a spring with a force constant of 23.9 N/m and whose mass is negligible. How far is the spring compressed if the bullet has a speed of 300 m/s just before it strikes the block and the block slides on a frictionless surface

Answers

Answer: 0.43 m

Explanation:

Given

mass of bullet [tex]m=10\ gm\approx 0.01\ kg[/tex]

mass of block [tex]M=1.95\ kg[/tex]

The Force constant of spring is [tex]k=23.9\ N/m[/tex]

Speed of bullet is [tex]u=300\ m/s[/tex]

Conserving the energy i.e. kinetic energy of the bullet and box is converted into Elastic potential energy of spring

[tex]\Rightarrow \dfrac{1}{2}(M+m)v^2=\dfrac{1}{2}kx^2[/tex]

Conserving linear momentum

[tex]\Rightarrow mu=(M+m)v\\\\\Rightarrow v=\dfrac{mu}{M+m}[/tex]

Put the value of [tex]v[/tex] we get

[tex]\Rightarrow x=mu\sqrt{\dfrac{1}{k(M+m)}}\\\Rightarrow x=0.01\times 300\sqrt{\dfrac{1}{23.9(0.01+1.95)}}\\\Rightarrow x=3\sqrt{\dfrac{1}{46.844}}=\dfrac{3}{6.844}=0.43\ m[/tex]

Thus, spring will be compressed to a distance of [tex]0.43\ m[/tex]

Calculate the momentum of a 10 kg bowling ball rolling at 2m/s towards north.

Answers

Answer:

momentum=mass x velocity= 10 x 2 = 20kgm/s

In a double-slit experiment, light from two monochromatic light sources passes through the same double slit. The light from the first light source has a wavelength of 640 nm. Two different interference patterns are observed. If the 10th order bright fringe from the first light source coincides with the 12th order bright fringe from the second light source, what is the wavelength of the light coming from the second monochromatic light source

Answers

Answer:

533.33 nm

Explanation:

Since dsinθ = mλ  for each slit, where m = order of slit and λ = wavelength of light. Let m' = 10 th order fringe of the first slit of wavelength of light, λ = 640 nm and m"= 12 th order fringe of the second slight of wavelength of light, λ'.

Since the fringes coincide,

m'λ = m"λ'

λ' = m'λ/m"

= 10 × 640 nm/12

= 6400 nm/12

= 533.33 nm

Lil' Ricky is trying on his Halloween costume in front of a flat (plane) mirror. Lil Ricky stands 1.5 m from the mirror.
Which statement correctly describes the image formed in the mirror?
A)
It is upright and 1.5 m behind the mirror.
B)
It is upright and 1.0 m behind the mirror.
C)
It is inverted and 1.5 m behind the mirror.
D)
It is inverted and 1.5 m in front of the mirror.

Answers

Answer:

The correct answer is A) It is upright and 1.5m behind the mirror

Explanation:

Your reflection must be upright, meaning vertical/erect, and the distance will be the exact same. Also, the reflected ray appears as if it had traveled from an object located behind the mirror.

Other Questions
21. Because of the American with Disabilities Act, all businesses: *(4 Points)have employees fluent in sign languageoffer occupational therapyhave wheelchair accessible entrancesO provide assistive devices for visitors Select ALL rational numbers below. The sum of the real numbers x and y is 11. Their differences is 5. What is the value of xy Determine the y intercept (8grade 30 POINTS!!!!! PLEASE ANSWER1. The Bolshevik Revolution of 1917 in Russia was caused in part by *a forced famine in Ukrainethe failure of Czar Nicholas II to come to Serbias aida shortage of military supplies and food during World War Ithe Sepoy RebellionOther:2. Joseph Stalins policies in Ukraine during the 1930s directly resulted in *agricultural self-sufficiencywidespread starvationthe development of cottage industriesthe use of subsistence farming techniques3.Which event led Russia to withdraw from World War I and surrender a significant amount of territory to Germany? *assassination of Austro-Hungarian Archduke Franz Ferdinandseizure of power by the Bolshevikssudden death of Vladimir Leninmeeting of the Yalta Conference4. A major purpose of five-year plans in the Soviet Union was to *increase the production of steel and machineryproduce more consumer goodseliminate central economic planningseek direct foreign investment5. A primary objective of the New Economic Policy (NEP) in the Soviet Union was to *promote private ownership of heavy industryorganize support for educational reforms to improve literacycoordinate efforts to end World War Igain stability by increasing production6. Which action was taken by the Bolsheviks under the leadership of Vladimir Lenin? *supporting a traditional economyeliminating political oppositionsurrendering to the Provisional Governmentextending the war against Austria-HungaryOther:7. Which goals are most closely associated with the Russian Revolution of 1917? *nationalism, democracy, and livelihoodscience, technology, and agriculturepeace, land, and breadliberty, equality, and fraternity8. One reason the Bolsheviks gained peasant support during the Russian Revolution was because the Bolsheviks promised to *abolish communesredistribute landbring modern technology to Russian farmsmaintain an agricultural price-support program9. What was a major reason the Russian people engaged in the Revolution of 1905? *failure to emancipate the serfsdiscontent with involvement in World War Idissatisfaction with czarist ruleirritation over the banning of the Orthodox church10. Totalitarian governments are characterized by the *elimination of heavy industryuse of censorship, secret police, and repressionlack of a written constitutionsupport of the people for parliamentary decisionsOther: Hi I need a lot of help writing something for my reading class the first sentence has to start with "Three of us. We were the only ones left, the only ones to make it to the island." Could some please help me, at least just on how to start. On the colorful map, in general, where is the youngest crust located? Krish and Aanya gor to a restaurant for dinner. Their meals total $13.75. The tax is 5%a. How much tax is added to the bill? b. Aanya and Krish want to leave a 15% tip based on their bill and tax combined. How much should they leave? Please answer this quickly The rectangle below has an area of 70 square meters. Find the dimensions of the rectangle. (x - 11) (x - 8) Which public issue is being debated?Group of answer choicesEqual pay for equal workSuffrageDrafting women into the militaryConstruction of more homeless shelters 10 , 1. A, B, C, D . 2 . ? A countrys population in 1990 was 145 million. In 1998 it was 151 million. Estimate the population in 2015 using the exponential growth formula. Round your answer to the nearest million What is one organ that a human can live without? a + 7a+3ab-2ab-1+6 Simplify Something you aim for that takes planning and work is a? Please help need at least 200 word essay about the effects before the civil war. PLS Will spent $40 at the fair. It cost $20 to get in the fair and $0.50 per ticket to ride the rides. How many tickets did Will buy? A. 40 B. 20 C. 120 D. 30 What is not the same as impeachment? *RecallReferendumCandidateInitiative A pharmacy technician just created his login and password for the pharmacys new computer system. Which best describes what he should do with the information?write it on a sticky note and place it in his desktell a fellow worker so someone else can help him rememberemail the password and user name to himself so he has it when neededmake sure he used information he can remember and do not write it down