# Physics!

74,459 results, page 6

1. ### Physics Plz help me

If a galaxy is traveling away from us at 2.0% of the speed of light, roughly how far away is it? t= light years I got 2.4x10^8 light years but its wrong please help me out...thank you Physics Plz help me - Anon, Monday, May 6, 2013 at 9:17pm 5.98x10^6 Thatz still wrong
2. ### Physics

You buy a plastic dart gun, and being a clever physics student you decide to do a quick calculation to find its maximum horizontal range. You shoot the gun straight up, and it takes 36.761s for the dart to land back at the barrel. What is the maximum horizontal range of your gun?
3. ### physics

Posted by Anonymous on Tuesday, December 2, 2008 at 12:43am. A loudspeaker is placed between two observers who are 114 m apart, along the line connecting them. If one observer records a sound level of 61.6 dB and the other records a sound level of 81.3 dB, how far is the ...
4. ### physics

ok i'm putting in physics it'll most likely change it watch A fisherman's scale stretches 2.8 cm when a 3.7-kg fish hangs from it. (a) What is the spring constant? (b) What will be the amplitude and frequency of vibration fi the fish is pulled down 2.5 cm more and released so ...
5. ### physics

Two small pith balls, each of mass m = 11.2 g, are suspended from the ceiling of the physics lab by 1.7 m long fine strings and are not moving. If the angle which each string makes with the vertical is è = 30.4°, and the charges on the two balls are equal, what is the ...
6. ### physics

Two small pith balls, each of mass m = 11.2 g, are suspended from the ceiling of the physics lab by 1.7 m long fine strings and are not moving. If the angle which each string makes with the vertical is è = 30.4°, and the charges on the two balls are equal, what is the ...
7. ### Physics

A large horizontal circular platform (M=143.1 kg, r=3.01 m) rotates about a frictionless vertical axle. A student (m=75.3 kg) walks slowly from the rim of the platform toward the center. The angular velocity ω of the system is 2.10 rad/s when the student is at the rim. ...
8. ### physics

We have to do a lab in physics where we research and write on real life applications of momentum, the guidelines we have are Research Assignment: Application of Momentum in Real-Life Situations Task: Choose any real-life situation where the concept of momentum is involved and ...

Hello, I'm totally lost on how to solve this physics problem. Where/how do I insert the variables?? "Light travels from one material with a refractive index (n1=1.5) to another material with refractive index (n2=1.7). If it strikes the surface at a 45° angle (it would also be...
10. ### Physics

What is the total force on the bottom of a swimming pool 27.5m by 9.0m whose uniform depth is 1.9m? physics What is the absolute pressure on the bottom of a swimming pool? What will be the pressure against the side of the pool near the bottom?
11. ### Physics

Can someone please help me sort out this problem? "A boy standing at the equator jumps vertically into the air. Does he land in the exact same spot after landing?" I'm thinking that when he jumps he is also moving horizontally with the earth and so he will land in the same ...
12. ### physics

A disgruntled physics student,frustrated with finals,releases his tensions by bombarding the adjacent building,17.7 m away with water balloons. He fires one at 38 degrees from the horizontal with an initial speed of 27.1 m/s. The acceleration of gravity is 9.8 m/s^2. for how ...
13. ### AP Physics

Jean, who likes physics experiments, dangles her watch from a thin piece of string while the jetliner she is in takes off from Dulles Airport (Fig. 4-55). She notices that the string makes an angle of 24° with respect to the vertical while the aircraft accelerates for takeoff...

in physics terms what does vacuum mean?? i thought they meant a vacuum sweeper?? huh? The question is " The same object is dropped in a vacuum and then in air. Whaich of the parameters( distance,velocity,acceleration) vary and which remain constant during succeding seconds of ...
15. ### physics

Posted by sandhu on Wednesday, November 24, 2010 at 4:29am. The firetruck goes around a 180°, 162 m radius circular curve. It enters the curve with a speed of 12.6 m/s and leaves the curve with a speed of 38.8 m/s. Assuming the speed changes at a constant rate, what is the ...
16. ### Physics

A 1200-kg automobile is stolen by the notorious Physics joyriders known as “the centripetal gang”. The gang tests their grasp on Newtonian physics by cruising around a banked circular track of radius 1025 m. From previous ‘experiments’ the gang has discovered the car...
17. ### Physics

Hey, have a question in Physics From a power magazine released 300,000 gallons of water pr.sekund into a pipeline leading to a turbine plant. Height difference between the magazine and the turbines are 300meter. The turbines provide 0.7 GW power. How large is the efficiency of...
18. ### PHYSICS

Hi! I have some questions from a study guide in my physics class, and they give me the answer, but I have to show how to get the answer. I did most of them, but need help with these. Here is problem #1: A skier with a mass of 60.0 kg is standing at the top of a snow covered ...
19. ### Physics

Physics question on identify the reaction? I am having trouble with the question a, b, and c in this physics problem: One or more external forces are exerted on each object enclosed in a dashed box shown in the figure below. Identify the reaction to each of these forces. (...
20. ### As physics

Please help and do it step by step all parts of questions and use: T = time(s) I=current (amps) Q=net charge on object (Coulombs) N=no electrons (and write if added or removed from object and how) E=elementary charge Calculate the number of free electrons per metre length of ...
21. ### Physics

In a demonstration in physics class, a 1.2 kg dynamics cart starts from rest at the top of a ramp. the ramp is 2.4 m above the ground. the cart then rolls down to the bottom of the ramp, where it collides with a stationary 1.4 kg dynamics cart. Assume that an elastic head-on ...
22. ### Physics

(a) Identify the significance of scientists James Clerk in hertz’s research. (b) Explain the physics of why hertz was able to detect sparkling in small detector coil when the detector was located in the position shown on the diagram above. (c) Describe two tests Hertz ...
23. ### venn diagram

venn diagram solving for 3 students likes geography physics science 75 likes only one subject 65 likes exactly two 15 like all three.1)how many students in a class 2)how many students like atleast one 3)how many students like only physics 4)how many students like only ...
24. ### Physics

Heyy is anybdy good at physics I am stuck on this question ... ... A camper van with a mass of 2500 kg has a maximum driving force of 2650 N. The camper van drives along a straight road at a constant speed of 90 kilomatres per hour. At this speed, air resistance is 2000 N and ...
25. ### Physics

I have to create a teaching aid for physics based on the principles i have learnt like gravitation , mechanical properties and many more. I am not able to find the right experiment to demonstrate infront of my teacher.Please help me deal with this by providing information ...
26. ### Physics

I have to create a teaching aid for physics based on the principles i have learnt like gravitation , mechanical properties and many more. I am not able to find the right experiment to demonstrate infront of my teacher.Please help me deal with this by providing information ...
27. ### Physics

The earth rotates once per day about an axis passing through the north and south poles, an axis that is perpendicular to the plane of the equator. (a) Assuming the earth is a sphere with a radius of 6.38 106 m, determine the speed of a person situated at the equator. My ...
28. ### Physics

Annie is walking to school leisurely at a speed of 1.0 m/s for the first half of her trip. She then remembers that her physics teacher told her that she must average 2.5 m/s to make it to school on time. Realizing she might be late, she starts running. However, after a quick ...
29. ### physics

Annie is walking to school leisurely at a speed of 1.0 m/s for the first half of her trip. She then remembers that her physics teacher told her that she must average 2.5 m/s to make it to school on time. Realizing she might be late, she starts running. However, after a quick ...

In a famous letter to Robert Hooke, Isaac Newton wrote, "If I have seen further it is only by standing on the shoulders of giants." Which of the following does this quote best demonstrate? (Points : 1) the cumulative nature of modern knowledge of physics how physicists form ...
31. ### math

if m set of 22 mathematics teachers and p is the set of 25 physics teachers and if 2 teachers both mathematics and physics, how many elements has MUP.
32. ### physics

You are watching an archery tournament when you start wondering how fast an arrow is shot from the bow. Remembering your physics, you ask one of the archers to shoot an arrow parallel to the ground. Unfortunately the archer stands on an elevated platform of unknown height. ...
33. ### physics

You are watching an archery tournament when you start wondering how fast an arrow is shot from the bow. Remembering your physics, you ask one of the archers to shoot an arrow parallel to the ground. Unfortunately the archer stands on an elevated platform of unknown height. ...
34. ### RE: PHYSICS

A man (weighing 915 N) stands on a long railroad flatcar (weighing 2805 N) as it rolls at 18.0 m/s in the positive direction of an x axis, with negligible friction. Then the man runs along the flatcar in the negative x direction at 40.00 m/s relative to the flatcar. What is ...
35. ### Physics

12 kg wagon is being pulled at an angle of 38o above horizontal. What force is applied to the wagon if it accelerates from rest to a speed of 2.2 m/s over a distance of 3.4 m? Is this question a typo? Am I supposed to solve for force or work? Physics - silverback, Tuesday, ...
36. ### Physics

physics - drwls, Sunday, January 24, 2010 at 2:50am Compute the angle of the strings from vertical. It is sin^-1 (8.5/40) Call this angle A If the string tension is T T sin A = F (the Coulomb force) T cos A = M g tan A = F/Mg You need to say what the units of the mass are. All...
37. ### physics

Im trying to study for my physics exam by doing some extra problems, however im stuck with this one. any help is much appreciated Two tiny spheres have the same mass and carry charges of the same magnitude. The mass of each sphere is 4.62 x 10-6 kg. The gravitational force ...
38. ### physics

It's a snowy day and you're pulling a friend along a level road on a sled. You've both been taking physics, so she asks what you think the coefficient of friction between the sled and the snow is. You've been walking at a steady 1.5m/s, and the rope pulls up on the sled at a ...
39. ### Physics

In a physics experiment, 250g of water is placed in a 50g calorimeter cup made of aluminum when both are at 15C. Steam at 100C is completely absorbed by passing it through the water, raising the temperature of water and cup to 45C. Find the mass of steam absorbed. Specific ...
40. ### Physics

In a physics experiment, 250g of water is placed in a 50g calorimeter cup made of aluminum when both are at 15C. Steam at 100C is completely absorbed by passing it through the water, raising the temperature of water and cup to 45C. Find the mass of steam absorbed. Specific ...
41. ### physics

Hello! I'm studying for physics and I am stuck on this question (I have the answer): Two identical cars are travelling on a horizontal road, one of them is going at twice the speed of the other one. Both break using the same force. The slower car breaks completely after 20m. ...
42. ### physics

A person throws a physics book off of a cliff at an initial speed of 3 m/s at an angle of 20 degrees. The book is in the air for a total of 2.5 seconds. a) How high is the cliff? b) How far away from the base of the cliff does the book land? c) What is the magnitude and ...
43. ### physics

In Physics, it is important to use mathemat- ical approximations. For instance, in a small angle approximation, tan α ∼ sin α . Find the largest angle α for which the dif- ference of sin α − tan α is less than 3.52% of the sin α value.
44. ### Physics

A block attached to a spring with unknown spring constant oscillates with a period of 7.0 s. Parts a to d are independent questions, each referring to the initial situation. What is the period if... The mass is doubled? The mass is halved? The amplitude is doubled? The spring ...
45. ### Physics - HELP PLS

A small dipole of length l with an input current Io radiates an electromagnetic wave that is TEM respect r with an electric field given by: E = j*w*Î¼*(1/2)*(Io*l/(4*pi))*e^(-jkr)/r * sinÎ¸ Find the expression of the magnetic field, the Poynting vector, the radiated power ...
46. ### Physics

Speedboat (A) negotiates a curve whose radius is 115 m. Speedboat (B) negotiates a curve whose radius is 240 m. Each boat experiences the same centripetal acceleration. What is the ratio vA/vB of the speeds of the boats? My physics optional extra work: This would be helpful so...
47. ### Physics

I have to compare and contrast three types of tires, and relate them to physics. I've chosen: <li> Racing tires <li> Winter tires <li> All season tires I've chosen to compare them on: <li> Tire tread pattern <li> Rubber compound <li> ??? As ...
48. ### Physics

A 0.340 kg particle moves in an xy plane according to x(t) = -15.00 + 2.00t - 4.00t3 and yet) = 25.00 + 7.00t - 9.00t2, with x and y in meters and t in seconds. At t = 0.700 s, what are (a) the magnitude and (b) the angle (relative to the positive direction of the x axis) of ...
49. ### Physics

A car is stationary at a stop sign when it is hit directly from behind by a truck of mass 3000kg which was travelling at a speed of 9 m/s immediately before the collision. The two vehicles lock together and move forward with an initial speed of 6 m/s. a) what is the mass of ...
50. ### Physics

A car is stationary at a stop sign when it is hit directly from behind by a truck of mass 3000kg which was travelling at a speed of 9 m/s immediately before the collision. The two vehicles lock together and move forward with an initial speed of 6 m/s. a) what is the mass of ...
51. ### physics

Need help with this short physics question there is a race betwen person A and person B. They both start at the same time, but B initial position is 10m left of peron A. person A travels 100 meters right in 20 seonds, Person Btravels 112.5 meters right in 15 seconds. what is ...
52. ### physics

Posted by michelle quendarsv on Saturday, November 20, 2010 at 3:55pm. if it takes 726 watts of power to move a mass 36 meters in 14 seeconds, what is the mass? i really need like, step by step help please? asap. thanks, michelle . physics - bobpursley, Saturday, November 20, ...

Two small pith balls, each of mass m = 11.2 g, are suspended from the ceiling of the physics lab by 1.7 m long fine strings and are not moving. If the angle which each string makes with the vertical is è = 30.4°, and the charges on the two balls are equal, what is the ...
54. ### Physics

Which of the following best describes kinematics? a) Kinematics is a part of mechanics that involves the description of motion. b) Kinematics is the branch of physics that deals with the motion of objects and the action of forces on the objects. c)Kinematics is the study of ...
55. ### physics

Apparent Weight. A physics student weighing 600 N stands on a bathroom scale in an elevator. As the elevator starts moving, the scale reads 420 N . A )Find the magnitude of the acceleration of the elevator. B ) Find the direction of the acceleration of the elevator.( up or ...
56. ### Physics - bobpursely

State the number of significant figures. 1) 809 Answer : 3 2) 0.0060 Answer : 5? 3) 0.00000095 Answer : 9? 4) 5.60 Answer : 3 5) 5.743 Answer : 4 6) 0.010 Answer : 4? Physics Help - bobpursley, Sunday, September 11, 2011 at 4:59pm 2, 3, 6 are wrong: Zeroes to the left of ...
57. ### Physics I for College

a rope that makes an angle of 30 degrees with the horizontal drags a crate along the floor. what must be the tension in the rope if a horizontal force of 40N is needed to drag the crate? please help me. i really didn't understand what my professor told me. he speak so fast. ...
58. ### Physics

Hello I am trying to solve this physics problem related to effusion of gases. The following data is given and I am asked to calculate the rate of effusion The data given; depth/thickness (t) Surface area (A) diffusion coefficient (D) Can someone help me out? The only law ...
59. ### physics

my physics teacher said that in simple harmonic motion of simple pendulum the direction of torque acting is opposite to angular displacement now i am wondering how ?as angular displacement is either anticlockwise or clockwise and torque direction is outward or inward to the ...
60. ### maths

1. A die labelled A has one face marked 1, one face marked 2 and the other four faces marked 3. A die labelled B has four faces marked 2 and two faces marked 3. The dice A and B are thrown. Calculate the probability is 5. I got 18/36 2. There are 12 boys and 20 girls in a ...
61. ### statistics

34. Two students (say A, and B) are challenged to solve a problem in statistics. Suppose that the probability that A will solve the problem is 40%, the probability that B will solve the problem is 55%, and the probability that A or B will solve the problem is 25%. The ...
62. ### Physics

I'm understanding most of this physics, but here is one last question I would appreciate help on. Thank you! Okay, so the question involves a figure. A link to the question and the picture with it is below can be found by googling the question along with Holt physics. The link...
63. ### Physics

A  serving  of  cereal  has  800 cal  (1 cal = .239 J).  How  far can  you  walk  with  this  energy?  Is  the  elapsed  time ...
64. ### physics

i need help understanding physics. im failing my class and don't want to do anything because i have zero clue where to start. im stuck on this problem currently. a cat pushes a ball from a 7.00 m high window, giving it a horizontal velocity of .20 m/s. how far from the base of...
65. ### SCIENCE ASAP

Hey just wanna to check this out that I'm pretty studying on Physics and Biology. Process Information is mos definitely I'm succeeding aight and it ain't that hard n'mean? I still all the stuff I gotta need to study. Send me a few ?'s on Process Information and most on Biology...
66. ### Physics

I am really confused on the steps to solve this problem. This is my first time taking physics. The much needed help, would be strongly appreciated. a) Calculate the centripetal force exerted on a vehicle of mass m = 1630 kg that is moving at a speed of 13.9 m/s around a curve ...
67. ### Physics

I came here earlier with this question: "A force of 20 N acts toward the west. Another force acts at the same point so that the resultant of the two forces is zero. What is the magnitude and direction of the second force?" I was wondering if someone could explain to me how to ...
68. ### math

A textbook store sold a combined total of 315 physics and chemistry textbooks in a week. The number of physics textbooks sold was two times the number of chemistry textbooks sold. How many textbooks of each type were sold?
69. ### physics

from what height should you drop your physics textbook so that it takes 0.2 seconds for it to fall? ftom what height would you drop a baseball so it takes 0.2 seconds for it to fall?
70. ### Physics

This is for physics class. Sally applies 32 N of force at an angle of 22 degrees above the horizontal to a 12 kg crate. Ignoring friction, calculate the horizontal acceleration of the crate? Conceptual: will the acceleration of the crate increase or decrease if the same force ...
71. ### Physics

A not so brilliant physics students wants to jump from their 3rd floor apartment window to the swimming pool below. The problem is the base of the apartment is 8.00 meters from the pool’s edge. If the window is 20.0 meters high, how fast does the student have to be running ...
72. ### physics

A 2.5 kg block of ice at a temperature of 0.0 degrees Celcius and an initial speed of 5.7 m/s slides across a level floor. If 3.3 x 10^5 J are required to melt 1.0 kg of ice, how much ice melts, assuming that the initial kinetic energy of the ice block is entirely converted to...
73. ### physics

Juan was on vacation in Italy, and one of this adventures, he went up the Pisa tower. He wants to know the tower height using Physics, so he drops a small stone that he has in his pocket and takes the time it lasts to reach the ground. What is the Pisa tower height according ...
74. ### physics

The human brain consumes about 23.7 W of power under normal conditions, though more power may be required during exams. How long can one candy bar (332 Calories per bar) power the normally functioning brain? (Note: The nutritional Calorie is equivalent to 1000 calories (1 kcal...
75. ### Physics Project

I am currently doing a physics project where I am launching a wooden pellet by using a sling into a container full of water. By changing the length the rubber band is stretched, I am measuring the pellet's submergence distance into water. I know that the velocity of the pellet...
76. ### physics

another question: the 20 kg block is at the top of a 10 m long inclined plane. The block starts from rest and slides without friction down the length of the incline. The block is 5 m high. 1) Determine the gravitational potential energy of the block at the top of the incline. ...
77. ### Physics

Pith Balls Two small pith balls, each of mass m = 17.7 g, are suspended from the ceiling of the physics lab by 0.8 m long fine strings and are not moving. If the angle which each string makes with the vertical is è = 42.6°, and the charges on the two balls are equal, what is...
78. ### Physics

I am trying to help my step son who missed half of physics class due to a funeral. A laser beam is being shot through two different materials that have been stuck together. if theta 1 = 65.5 and theta 2 = 49.8 what is the index of refraction? (I got 1.2 which is correct) but ...
79. ### Physics

I know I need to show my work but the problem is that I don't even know where to begin. I am taking an online physics class with a teacher that is not willing to help. So any guidance would be much appreciated. Consider the two vectors: F1: (220N, 41°), F2: (50N, 139°) The ...
80. ### Physics

Two geekie physics students with a combined mass of 131 kg jump into their old car to run out for some late night pizza. The distance between the front and back axles of the car is 2.9 m. When they get in the car, the springs compress a total of 9.3 cm. On their way to the ...
81. ### Math

in a class of 60 students 30 like maths 25 like physics 30 like chemistry. if 10 like both physics and maths 5 like maths and chem and 5 like phy & chem and 3 like all the subjects. find student like none of subject of if 100 students were surveyed
82. ### Math

in a class of 60 students 30 like maths 25 like physics 30 like chemistry. if 10 like both physics and maths 5 like maths and chem and 5 like phy & chem and 3 like all the subjects. find student like none of subject if 100 students were surveyed
83. ### physics

hello everyone...i just has a general question. I am trying to study for physics. The chapter is contains potential energy, conservative, non conservative, kinetic energy. They have a definition of each , but i still don't have a better understanding of them. I cant ...
84. ### physics

In preparation for a demonstration on conservation of energy, a professor attaches a 7.2-kg bowling ball to a 3.4-m-long rope. He pulls the ball 23° away from the vertical and holds the ball while he discusses the physics principles involved. Assume that the force he exerts ...
85. ### physics

what is the physics behind the process of administering the following 1. measurement of blood pressure using sphygmomanometer 2.giving injections 3.administering intravenous infusion 4.giving oxygen in the ward and operating theater 5. administering blood transfusion 6.sucking...
86. ### Physics

12th grade physics ap question. A baseball with a mass of 120 g is hit 21.8 m into the air. The ball is caught by the third baseman 2.5 m above the ground. What potential energy did the ball develop at its highest point? How much potential energy did it still have when it was ...
87. ### PHYSICS

Hi! I have some questions from a study guide in my physics class, and they give me the answer, but I have to show how to get the answer. I did most of them, but need help with these. Here is problem #8: A 20 kg block of ice slides without friction down a long hill. The start ...
88. ### physics

what is the answer to the following 2 physics equations: a=(v, little f in right bottom corner -v little 0 in bottom right corner /t. I need it simplified to what t is and T^- 2n into the square root of L/g I need the equation simplified to get g
89. ### Physics

Right now in physics we are learning about electric potential energy and electric potential. My question is: P and Q are points within a uniform electric field that are separated by a distance of 0.1 m. The potential difference between P and Q is 50 V. How much work is ...
90. ### physics

A 1.6 kg particle moving along the x-axis experiences the force shown in the figure. The particle's velocity is 4.2 m/s at x = 0 m. The figure or graph has F (N) along the y axis and velocity along the x axis. A diagonal line drops from positive 10 force to -10 force from 0 cm...
91. ### As physics

The table below shows how the braking distance x for a car depends on its initial speed u u / ms-1 5.0 10 20 4 x / m 2.0 8.0 32 128 the reaction time of a driver is 0.60s. Calculate the sopping distance of the car when u= 30ms-1. The mark scheme says: Thinking distance= 30 X 0...
92. ### Physics

A dock worker applies a constant horizontal force of 79.0 N to a block of ice on a smooth horizontal floor. The frictional force is negligible. The block starts from rest and moves 11.0 m in the first 6.00 s. What is the mass of the block of ice? *I notice two very common ...
93. ### physics

1. You are planning to build a mini hydro power plant. A river near your home is w = 4.0 m wide and h = 1.0 m deep. You measure the water flow to be v = 1.50 m/s over the brink of a waterfall H = 10.0 m high. The company that makes the turbine advertises e = 25% efficiency in ...
94. ### Physics

i have been asking physics questions on this and some people give me the formula, i'm getting the correct answers..please can the same people help me on this that helped me before.. A child rides a bicycle in a circular path with a radius of 2.0 m. The tangential speed of the ...
95. ### Re: PHYSICS

A man (weighing 915 N) stands on a long railroad flatcar (weighing 2805 N) as it rolls at 18.0 m/s in the positive direction of an x axis, with negligible friction. Then the man runs along the flatcar in the negative x direction at 40.00 m/s relative to the flatcar. What is ...
96. ### Writeacher

Writeacher, Do you specialize in any particular subject? I've seen you answer to math, english, physics, etc. I'm just curious. I don't believe I've answered to any physics questions -- poor student to depend on me for that!! Mostly I respond to English questions (grammar, ...
97. ### physics

a sea saw consist of a uniform bar 4m long and of mass 2kg. a boy of weight 42N sits at end of the sea saw while another boy of weight 38N sits at the end of the season. at what point must the season be pivoted if it is to balance. according to physics
98. ### Physics

The human brain consumes about 21.3 W of power under normal conditions. (More power may be required during exams...) How long can a candy bar (299 Calories) power the normally functioning brain? Note: The nutritional Calorie is equivalent to 1000 calories, or 1 kcal, as ...
99. ### PHYSICS

I'm having some trouble with a problem on my physics pre-exam, if there is any formula please let me know so i can do a bit of research on it. any help is greatly appreciated in advance. The inner membrane of a cell membrane is negative relative to the outer surface. if 1.6 X ...
100. ### college physics

In Physics we often use meters per second as the units of velocity, rather than miles per hour. Convert 1 meter per second to miles per hour to get an idea of how these units compare. Please help me by showing me step by step so I can understand it better.