# physics please HELP !

129,562 results, page 31

### physics

i REALLY don't get this problem. PLEASE HELP!!! the position of a runner during a 3 second time interval the runners position changes from x1 = 50m to x2 = 30.5m what was the runners average velocity? find the average speed as well as the average velocity.

### PHYSICS PLEASE HELP

A satellite has a mass of 5850 kg and is in a circular orbit 4.50 x 10^5 m above the surface of a planet. The period of the orbit is two hours. The radius of the planet is 4.20 x 10^6 m. What is the true weight of the satellite when it is at rest on the planet's surface?

### Physics

A block of aluminum that has dimensions 2.07 cm by 2.55 cm by 5.00 cm is suspended from a spring scale. The density of aluminum is 2702 kg/m^3. (a) What is the weight of the block? 0.699 N (b) What is the scale reading when the block is submerged in oil with a density of 817 ...

### Math

PLEASE PLEASE HELP ME WITH THESE 2 PROBLEMS STEP BY STEP AND SHOW WORK! z/12=9 what is the value of z show how you found it. 5 x g= 230 what is the value of g show how you found it. PLEASE I REALLY NEED HELP!!!

### Physics

A heater cansupply 98000J an hour. If a lot of ice is already at 0 degrees, how much ice can be turned to water? check my work please: Q/l=m 98000J/kg / 3.35 * 10^5J = 029kg of ice can be turned to water

### Physics - Rube Goldberg Project

I need to make a Rube Goldberg Machine and it must demonstrate projectile motion, conservation of energy and conservation momentum, any idea on what to make and how to make it? Help please

### Physics-Help Please!

a 25gram bullet is fired upward through a .36kg block. the block goes up 17cm in the air and the bullet goes up 24m into the air. What is the initial velocity of the bullet?

### Physics Please

A boy on a swing is pulled to a position 2.34 m off the ground and released. At the fastest and lowest point of the swing the boy is 0.50 m off the ground and travelling 3 m/s. The percent efficiency of this swing system is?

### Physics

Calculate amount of energy needed to completely vaporize a 50g piece of 20 degree C silver melting point 1064 C L(f) = 64KJ/Kg Boiling point 2856C L(v) = 1645 KJ/Kg c= 0.13KJ/Kg degrees C I'm thinking I balance each side to equal each other but I'm not dure-I've done specific ...

### reading

sentense with 11 elephant Please keep in mind that we don't do students' homework for them. Once you write a sentence, please re-post and someone here will let you know if you're right or need to work on it some more. =)

### pre-cal/trig

PlEASE help me with this!! I need it as soon as possible....... cos(x-(pi/4))+sin(x-(pi/4))=1 Find the answer from 0 to 2pi. When I slove this, I got cosx+sinx=(1/ square root of 2). then I don't know what to do the rest. Please help me.

### Ms. Sue please

Could you please clarify what your intentions were behind what you said on Friday the 24th in a thread that was marked as "society"? The time stamp was 2:22. I have already left my own personal interpretation there.

### PLEASE AND THANK U

i just want to sat that I appreciate all u teachers helping me, but please don't provide one site for me which is Wikipedia. I don't understand a single thing wen I reach that page. It confuses me more, but thanx

### calculus please help

I posted this below but had no response. I would appreciate help with details please.How do I find the indefinite integral of h(u)=sin^2(1/5u) this is one fifth u. Does it involve double angle formulas? Thanks.

### calculus--please helpp

if the line 3x-4y=0 is tangent in the first quadrant to the curve y=x^3+k, find k. all i know is that its related to finding a derivative and i m basically completely lost....can please someone provide me some help?????

### pre-calc HELP PLEASE

solve using identities for all angles (dont use multiple angle method)show work please cuz i am so confused. 2sin2x-3sinx=0

### matt/116

Will someone please help me find the answer to this question please. How do you write a system of linear equations in two variables? Explain this in words and by using mathematical notation in an equation.

### social studies

3 things in history that impacted in south America,europe,asia,africa and austrlia.(please list all and I can do the rest) P.S please get back to me by tomorrow before 2 o' clock

### Language Arts

Please help me with the following: Myths often function as a connection to __________, or the customs and beliefs of a group of people. I think the answer is phenomena, but I don't even know if that is correct. Please help me, any help will be appreciated.

### math algebra

COULD SOME OF WITH DEGREE IN MATHS HELP ME TO SOLVE THIS SIMULTANEOUS EQUATION PLEASE, PLEASE ? I HAVE RIED DIFFERENT METHODS BUT IT CANNOT GET THE CORRECT ANSWER, AS IN THE BOOK. X-3/4 -Y-2/5 = -1/4 (1) 4-X/3+ 3-Y/2 = - 13/20 (2) 5x-15-4y+8= -1 5x-4y=17-1 8-2x+9-3y= -13 -2x-...

### English

Two students talked about the title. Now, one last student....OK. Well done. Please remain quiet, everyone. ------------------- Would you check the short passage? Correct any errors, please.

### Social studies please help soon I'm timed please

Which religion considers the epic poem about Krishna one of the most important texts? A: Buddhism B:Hinduism C: judaism D: Zoroastrianism

### Pre calc

Please help me proof the identity. This isn't even math to me, I can not understand it so please show all work. God bless A)1-cos2x/sin2x=tanx B) sin4x/sinx=4cosxcos2x

### graphic design please help

i tried to find the answer but i come up with nothing please help any links or any thing will be helpful In 1-2 paragraphs describe the importance of prioritizing your focus when designing for multiple purposes

### Language Arts

I need help please! Compare and contrast two of the following forms of poetry: limerick, haiku, concrete. Give specific examples of each of the poems. Its in a quiz, hurry up please!

### physics

A ball of moist clay falls to the ground from a height of 19.8 m. It is in contact with the ground for 19.0 ms before coming to rest. What is the average acceleration of the clay during the time it is in contact with the ground? (Treat the ball as a particle.) PLEASE HELP! :)

### Physics (Please help!!!)

1) An ideal gas occupies a volume of 0.60 m^3 at 5atm and 400K. What volume does it occupy at 4.0atm and a temp of 200K? I know how to find the volume with the m^3 and the atm but it threw me off since it gives the 4.0 atm and the temp 200K.

### physics. please help!

A 2.5 kg block is pulled to the right by a horizontal string. The coefficient of static friction between the block and the floor is 0.30 and the coefficient of kinetic friction is 0.20. What value of force applied by the string will start the block moving?

### Physics

A sample of serum has a mass of 54 gm and a volume of 225cm. What's the density in g/cm? I think the answer is .24g/c please correct me of I'm wrong but my ? is what would be the mass of 150 fluid ounces of this serum? What would be the volume of 1 pound of this serum?

### Physics PLEASE HELP

A 50-kg crate is pulled across the ice with a rope. A force of 100 N is applied at an angle of 38° with the horizontal. Neglecting friction, calculate the acceleration of the crate AND the upward force the ice exerts on the crate as it is pulled.

### Physics Please

A tennis player places a 51 kg ball machine on a frictionless surface, as shown below. The machine fires a 0.067 kg tennis ball horizontally with a velocity of 33.4 m/s toward the north. What is the final velocity of the machine?

### Physics

11. An object with a charge of +6.0 µC is 0.30 m from a second object and experiences an attractive force of 1.80 N. What is the magnitude of the charge on the second object? (µC = 1.0 × 10-6 C) (Answer: -3.0 µC) Can someone please explain how to do this problem? I don't ...

### physics. urgent answer please

Two forces 10 N acting in the direction N 30 east and 15 N acting in the eastern direction, if both forces act at a point, find the magnitude and direction of (a) the resultant force (b) the equilibriant force.

### Physics

A liter of water is used to cool some electronics. If 1000 J of heat is given off by the electronics, by what temperature does the water increase? One liter of water has a mass of 1 kg and a specific heat of 4.184 J/(g °C). I can not get this..please help

### PHYSICS

The masses and coordinates of four particles are as follows: 40 g, x = -4.0 cm, y = 5.0 cm; 30 g, x = 5, y = 0.0 cm; 40 g, x = –5.0 cm, y = 3.0 cm; 20 g, x = 3.0 cm, y = 2.0 cm. What are the rotational inertias of this collection about the (a) x, (b) y, and (c) z axes? >&...

### physics-repost

An owl has good night vision because its eyes can detect a light intensity as small as 5.0*10^-13W/M^2. What is the minimum number of photons per second that an owl eye can detect if its pupil has a diameter of 8.5nn and the light has a wavelength of 510nm? Can anyone please ...

### Physics - Important

a car attempts to stop and slides 25.5m while accelerating at -4m/s^2. The car's initial velocity was 20m/s. Find the time the slide took. Note that the final velocity is not known and that you need a quadratic solution. I know the quadratic formula, but I'm not sure how to ...

### physics

in an emergency stop to avoid an accident, a shoulder-strap seat belt holds a 60kg passengr firmly in place. if the car was initially travelling at 90km/h and came to a stop in 4.5s along a straight, level road, what was the average force applied to the passenger by the seat ...

### Physics-Please check

If I had the old-fashion camera that had a focal length of 35mm(0.035m) and I take a picture of a person 6 m away, how far does the film need to be from the lens to record a clear image? I know that the equation is 1/f = 1/d(object) + 1/d(image) so would I do the following: 1/...

### Physics; help please :)

Two wires made of the same material of density 7240 kg/m3 and having the radius in the ratio 1:2 but the same length 1.54 connected together and stretched by a force of 540 N. If the speed of a transverse wave through the thinner wire is 3600 m/s, calculate the wave velocity ...

### AP Physics

An electric furnace runs nine hours a day to heat a house in January (31 days). The heating element has a resistance of 10.6 ohms and is hooked up to a 240 Volt potential. What does it cost to run the furnace in the month of January if the cost of electricity is $0.15 per KW*...

### Physics help please

excited by the in class experiments you put two speakers in your living room 80cm apart producing a sound of 750Hz. 4.0 m away you place a microphone right on the centerline between the speakers. Will the microphone detect a loud sound or a soft on at this point (relatively to...

### College

Does Harvard University have art & creative writing classes cause I want to become a artist & a creative writer (when writing books, short stories, novels, & poems). I'm just asking. I look on the website but it really confusd me. Please also what is REALLY Harvard Uninersity...

### physics

HELP PLEASE!!! A satellite moves in a circular orbit around Earth at a speed of 5085 m/s. (a) Determine the satellite's altitude above the surface of Earth. (b) Determine the period of the satellite's orbit.

### English Survey(please post)

what book do you think should be made into a movie? and why?(please state reason clearly.) consider the questions below: what's the benefit if it was made into a film? is there something that you think can be presented in the movie better than the book? why do you think people...

### Math

How do you work this problem step by step? p-12 when p= 22 We don't know what book you are using and probably none of us has a copy if you told us the name of the book. Please post your question and someone will try to help. Please be specific and tell us exactly what you don'...

### physics help please!

The motion of a piston in an auto engine is simple harmonic. The piston travels back and forth over a distance of 23 cm, and the piston has a mass of 1.7 kg. 2515 rpm 23 cm max speed of the piston 30.28757 m/s What is the maximum force acting on the piston when the engine is ...

### Physics

Help me with this please A 6.0 m section of wire carries a current of 5.2 A from east to west in the earth's magnetic field of 1.0 × 10^-5 T at a location where the magnetic field points south. In which direction does the magnetic force act on the wire? north south up down

### physics

An object uniformly accelerates at a rate of 1.20m/s^2 east. While accelerating at this rate, the object is displaced 470.4m east in a time of 28 s. What velocity did this object reach in this time ? I used Vf=Vi+at which will be Vf=(1.20)(28) but i feel this isn't the way to ...

### physics

There is motion of a straight track between two stations. Average speed: 12m/s Distance between stations: 3600m. Please help how could I find the max speed given these information? and it isn't like the average speed so it confused me

### Physics-HELP PLEASE

If I'm driving a car and I make a turn to the right, what will happen to a bag of items that is sitting next to me in the car-in terms of inertia, friction and centripetal force I think they will fall the opposite direction but we just started this unit and I don't what ...

### Physics

Please help ~ Two blocks are arranged at the ends of a massless string as 3.21 kg (box hanging from table) 4.96 kg (box on table). The system starts from rest. When the 3.21 kg mass has fallen through 0.4 m, its downward speed is 1.27 m/s. The acceleration of gravity is 9.8 m/...

### Physics

A winch with a power rating of 400 W lifts a 200kg object off the ground at a constant velocity for 17 seconds. How high was the object lifted? What is the object total energy? Please indicate which equation you use, what variable corresponds to each number, and how you got ...

### physics

Two 4.0-g spheres are suspended by 9.0-cm-long light strings (see the figure). A uniform electric field is applied in the x-direction. If the spheres have charges of −3. 10-8 C and +3. 10-8 C, determine the electric field intensity that enables the spheres to be in ...

### PHYSICS

A 9.5-kg watermelon and a 7.2-kg pumpkin are attached to each other via a cord that wraps over a pulley, as shown. Friction is negligible everywhere in this system. Pumpkin is at left of angle n is 53 degrees and watermelon is on right and at 30 degrees calculate acceleration ...

### Physics

A 9.5-kg watermelon and a 7.2-kg pumpkin are attached to each other via a cord that wraps over a pulley, as shown. Friction is negligible everywhere in this system. Pumpkin is at left of angle n is 53 degrees and watermelon is on right and at 30 degrees calculate acceleration ...

### Physics

A 9.5-kg watermelon and a 7.2-kg pumpkin are attached to each other via a cord that wraps over a pulley, as shown. Friction is negligible everywhere in this system. Pumpkin is at left of angle n is 53 degrees and watermelon is on right and at 30 degrees calculate acceleration ...

### Physics

A 9.5-kg watermelon and a 7.2-kg pumpkin are attached to each other via a cord that wraps over a pulley, as shown. Friction is negligible everywhere in this system. Pumpkin is at left of angle n is 53 degrees and watermelon is on right and at 30 degrees calculate acceleration ...

### Physics

If two protons and two neutrons are removed from the nucleus of an oxygen-16 atom, a nucleus of which element remains? Carbon 12 will be the answer, but i need to understand the answer. I requested help from a friend but was given the answer and not explained. I am having a ...

### physics

Please help me answer the question because I am really confused about this problem. 1. an electron in a one-dimensional box undergoes a transition from the n=3 level to the n=6 level by absorbing a photon of wave length 500 nm. what is the width of the box? 2. what is the ...

### Physics

Please help! Any advice is appreciated A water faucet in a house is h=8 m below the water surface in the local water tower. The radius of the orifice in the fully opened faucet is r=0.01 m. We assume non-viscous flow in this problem. a) How long does it take to fill a 20 liter...

### physics

Ok. I'm writing that big test tomorrow, and I have no idea what should I do with this : An alien is 5m from an astronaut. The astronaut notices the alien and they simultaneously begin to run from each other with v[alien]= 2m/s and v[astronaut] = 4m/s. Find their mutual ...

### Physics

Hello, my problem is the next one: There are three objects that are launched at the Same time But with different angles( they describe proyectile motion ) . All the objects got the Same maximun height. My question is: Is the Initial velocity the Same for the three objects? Why...

### physics

a photon whose energy equals the rest energy of the compton collision with an electron, if the electron moves off an angle of 40 degrees to the original photon direction, what is the energy of the scattered photon? assume all constant given. please i need an answer.

### physics

A runner training for a race times 400 meter laps. Lap 1 60sec, Lap 2 57sec, Lap 3 55sec, Lap 4 53sec. What is the average velocity in meters per second? a. 0.563 b. 7.1 c. 14.2 d. 56.25 please help me, I using the average velocity formula but still i get it wrong

### physics

Please help! it has to do with momentum A 70 k/g woman and her 35 k/g son are standing at rest on an ice rink. They push against each other for .60 s, causing them to glide apart. The speed of the woman immediately after they separate is .55 m/s question asks what is the ...

### maths/physics

Please I need some help with this question A cicular opaque disk, 25cm in diameter, is set up 30 cm from a circular source of light of diameter 40 cm. A screen is placed 30cm beyond the opaque disk. Describe, giving dimensions, the nature of the shadow on the screen.

### Physics. PLEASE HELP!

two blocks of masses m1 and m2 (m1>m2) are placed on a frictionless table in contact with each other. A horizontal force of magnitude F is applied to the block of mass m1. if P is the magnitude of the contact force between the blocks, what are the net forces acting on m1 ...

### Physics. Easy question? Please help

What is the (a) maximum and (b) minimum total resistance value that can be obtained using three resistors whose values are 2.0 ohms, 4.0ohms and 6.0 ohms? The resistors can be used individually, in pairs, or all three at once. Is this a trick question? Is the answer 12 and 2?

### physics ..PLEASE HELP ASSIGN DUE SOON :(

The sound intensity of 1.2x10-12J/m2s is the threshold of hearing for humans. What is the amplitude of the motion of the air molecules if the speed of sound in the air is 343m/s and the density of air is 1.28kg/m^3? Take the frequency of the air molecules as 1000 Hz

### Physics- Please Help, soooo lost!

Two pipes of equal length are each open at one end. Each has a fundamental frequency of 715 Hz at 300 K. In one pipe the air temperature is increased to 313 K. If the two pipes are sounded together, what beat frequency results?

### Physics Important please

Four charges are arranged at the corners of a regular tetrahedron (a pyramid with four sides that are identical equilateral triangles). The charges are 1 Coulomb each, and the sides of the tetrahedron are all 1 meter. How much energy in Joules is required to assemble this ...

### physics

How much positive charge is in 0.8 kg of neon? The atomic weight (20.1797 g) of neon contains Avogadro’s number of atoms, with each atom having 10 protons and 10 electrons. The elemental charge is 1.602 × 10−19 C and Avogadro’s number is 6.023 × 1023 . Answer in ...

### Physics

A block with a mass of 0.357 kg is attached to a spring of spring constant 599 N/m. It is sitting at equilibrium. You then pull the block down 4.80 cm from equilibrium and let go. What is the amplitude of the oscillation? I know A=D/F... I keep getting the wrong answer though...

### Physics

A 25 kg box is along a horizontal floor and a force of 400 N pushes the box with an angle of 50 degree with the horizontal. Starting from rest, the box achieves a velocity of 2 m/s in a time of 4 seconds. Find the coefficient of sliding friction between the box and the floor. ...

### Physics

An ion beam has a cross-sectional of 2.5 mm^2 and the charge delivered by it to a target can be expressed as q(t)=(.12 C/s^3)t^3 + (.24 C/s^2)t^2 - .45 C. Calculate the current density in the beam at t = 3.0 seconds. I used an integral from 0 to 3s. and got 3.24C, then I ...

### Physics

A passenger on a ride at the firemen's field days sits in a chair and is swung around at the end of a cable connected to a central tower. At full speed, the cable makes an angle of 56o with the vertical, and the chair is 46 m from the pole. 1)What is the speed of the passenger...

### Physics

A passenger on a ride at the firemen's field days sits in a chair and is swung around at the end of a cable connected to a central tower. At full speed, the cable makes an angle of 56o with the vertical, and the chair is 46 m from the pole. 1)What is the speed of the passenger...

### physics please help

A golfer, driving a golf ball off the tee, gives the ball a velocity of +40 m/s. The mass of the ball is 0.045 kg, and the duration of the impact with the golf club is 4.05E-3s. (a) What is the change in momentum of the ball? (b) Determine the average force applied to the ball...

### Physics

Town A lies 20 km north of town B. Town C lies 13 km west of town A. A small plane flies directly from town B to town C. What is the displacement of the plane. Please explain how you got the answer

### Physics

Please Help! I am having difficulties grasping these concepts. Explain please! 1. How much heat energy is required to change 500 grams of water at 100 degrees Celsius to steam at 100 degrees Celsius? 2. How much energy is lost if 7kg of water is cooled from 46 degrees Celsius ...

### physics - please help

A 0.455 kg wood block is firmly attached to a very light horizontal spring (k = 160 N/m). It is noted that the block-spring system, when compressed 5.0 cm and released, stretches out 2.3 cm beyond the equilibrium position before stopping and turning back. What is the ...

### physics - please help

A 0.455 kg wood block is firmly attached to a very light horizontal spring (k = 160 N/m). It is noted that the block-spring system, when compressed 5.0 cm and released, stretches out 2.3 cm beyond the equilibrium position before stopping and turning back. What is the ...

### Physics

Why is there a centripetal acceleration if the velocity does not increase? a. Velocity changes direction as you move around the circle, causing a Δv b. Velocity in a circle is always constant c. Because gravity will hold any object in a circular motion I am almost sure ...

### Physics

I am reviewing for a test and I don't know how to attempt this question. Could someone please work through this problem and then have the general steps that I need to take to solve the question? Here is the question: A rocket expels gases at a rate of 1.30 x 10^3 kg/s with a ...

### Physics

I am reviewing for a test and I don't know how to attempt this question. Could someone please work through this problem and then have the general steps that I need to take to solve the question? Here is the question: A rocket expels gases at a rate of 1.30 x 10^3 kg/s with a ...

### Physics

I am reviewing for a test and I don't know how to attempt this question. Could someone please work through this problem and then have the general steps that I need to take to solve the question? Here is the question: A rocket expels gases at a rate of 1.30 x 10^3 kg/s with a ...

### Science Physics

Projectile motion problem. The maximum range for a projectile is achieved when the projectile is fired at 45 degrees. This is true if the launch starts and ends at the same altitude. What about if you fire at a target at a lower elevation? Is the optimal angle still 45 degrees...

### physics

It is possible to shoot an arrow at a speed as high as 100 m/s. (a) If friction is neglected, how high would an arrow launched at this speed rise if shot straight up? (b) How long would the arrow be in the air? Please help! I do not have any clue as to how to solve. Thanks!

### physics

A daredevil is shot out of a cannon at 43.0° to the horizontal with an initial speed of 25.0 m/s. A net is positioned a horizontal distance of 50.0 m from the cannon. At what height above the cannon should the net be placed in order to catch the daredevil? please walk me ...

### please help me, physics

Five moles of a monatomic ideal gas expand adiabatically, and its temperature decreases from 410 to 200 K. (a) What is the work done by (or done to) the gas? Include the algebraic sign. J (b) What is the change in the internal energy of the gas? Include the algebraic sign. J

### Physics(Please help)

1) A cave explorer drops a stone from rest into a hole. The speed of sound is 343 m/s in air, and the sound of the stone striking the bottom is heard 1.33 s after the stone is dropped. How deep is the hole? I did 343 / 1.33. Is this correct?

### physics

The length and breadth of a rectangular sheet are 16.2 cm and 10.1cm, respectively. The area of the sheet in appropriate significant figures and error is (a) 164 ± 3 cm2 (b) 163.62 ± 2.6 cm2 (c) 163.6 ± 2.6 cm2 (d) 163.62 ± 3 cm2 please explain me what is the correct ...

### Physics

In the double slit experiment with light, we know that the spacing of the interference fringes (which is what we call the bright spots on the screen) depends on the wavelength of the light. How? Specifically, if you make the wavelength of the light bigger, how does the spacing...

### Physics(Please help)

using the equation y=yo + (vo sin Q) t - 1/2gt^2 I have to find t. The values for y, yo and vo were given to me. So I set the equation up like this: 0=1.005 + (3.107 sin 0) t - 1/2(9.8)(t^2 The sin of 0 is 0 times 3.107 is 0. So 0 = 1.005 t - 4.9 t^2 Now I am stuck. I am not ...

### physics

Assume that there is no friction between m2 and the incline, that m2 = 1.8 kg, m1 = 1.4 kg, the radius of the pulley is 0.10 m, the moment of inertia of the pulley is 3.6 kg m2, and θ = 27.0°. Mass 1 is hanging vertically while mass 2 is on the incline. After mass 2 has ...

### physics

Assume that there is no friction between m2 and the incline, that m2 = 1.8 kg, m1 = 1.4 kg, the radius of the pulley is 0.10 m, the moment of inertia of the pulley is 3.6 kg m2, and θ = 27.0°. Mass 1 is hanging vertically while mass 2 is on the incline. After mass 2 has ...

### please help physics

parallel plate capacitor has an area of 5cm^2 and a capacitance of 3.5PF. the capacitor is connected to a 12v battery .after the capacitor is completely charge up the battery is removed. a)what must be the separation of the plates and the charge density on the plate

### Physics

A mass (0.5 kg) and spring (k = 250 N/m) system oscillates with an amplitude of 3.5 cm. a) What is the total mechanical energy of the system? b) What is the maximum speed of the mass? c) What is the maximum acceleration of the mass? I need help please! Do it step by step and ...