# physics please HELP !

127,101 results, page 29

### Physics

A cart of mass M1 = 4.00 kg and initial speed = 4.00 m/s collides head on with a second cart of mass M2 = 2.00 kg at rest. Assuming that the collision is elastic, find the speed of M2 after the collision. i keep getting the wrong answer please help me.I don't know what ...

### 11th grade: Physics

For each pair of frequencies below, calculate the ratio of their frequencies as a simple fraction, then determine which pair has the higher dissonance. a) 261.6 Hz and 392 Hz b) 349.2 Hz and 392 Hz I just don't know how to make these into simple fractions. Please help me

### Physics

How does mass effect a free falling object? I was thinking that if the mass is greater then object would have a higher acceleration because due to it's weight it would have less drag on it from the air. Something of that sort. Could someone else this to me please.

### physics

(a) What is the gravitational potential energy of a two-particle system with masses 5.4 kg and 5.0 kg, if they are separated by 1.3 m? If you triple the separation between the particles, how much work is done (b) by the gravitational force between the particles and (c) by you...

### Physics Year 7 (Help please)

Isabella drops a chunk of iron of mass m from the roof of her high school and it accelerates at g. Then she ties two chunks of iron together of mass 2m. Show that when she drops the double chunk, the acceleration of fall is also g. Thank you :)

### physics

At a low point in its swing, a pendulum bob with a mass of 0.2kg has a velocity of 4m/s. Ignoring air resistance, how high will the bob swing above the low point before reversing direction? Please explain and show work.

### physics

A hot iron horseshoe (mass = 0.43 kg), just forged (Fig. 14-16), is dropped into 1.60 L of water in a 0.26 kg iron pot initially at 20°C. If the final equilibrium temperature is 26°C, estimate the initial temperature of the hot horseshoe. Could someone please help me out ...

### Physics

A 7.9cm diameter horizontal pipe gradually narrows to 5.9cm . When water flows through this pipe at a certain rate, the gauge pressure in these two sections is 31.0kPa and 21.0kPa , respectively. What is the volume rate of flow? in m3/s please help!

### Physics please help!!

A basketball player throws the ball at a 38° angle above the horizontal to a hoop which is located a horizontal distance L = 5.6 m from the point of release and at a height h = 0.4 m above it. What is the required speed if the basketball is to reach the hoop? Not sure how to ...

### physics

A satellite with mass 6.00*10^3 is in the equatorial plane in a circular orbit. The planet's mass = 6.59 *10^25 and a day of length is 1.6 earth days. How far from the center (in m) of the planet is the satellite? What is the escape velocity (km?sec) from the orbit? please ...

### Physics PLEASE HELP!

A bullet whose mass is 1.0 x 10-3 kg leaves a 5.0 kg rifle with a muzzle velocity of 1.0 x 103 m/s. It strikes a stationary block of wood whose mass is 1.0 kg and remains embedded in it. The kinetic energy of the bullet as it travels towards the wooden block is?

### Physics

Suppose a soccer player kicks the ball from a distance 31 m toward the goal. Find the initial speed of the ball if it just passes over the goal, 2.4 m above the ground, given the initial direction to be 44° above the horizontal. Help please !

### physics

A boxcar of mass 3.21 x 10^4 kg is rolling south at 5.16 m/s when it collides and couples with another boxcar of mass 5.18 x 10^4 kg that is rolling north at 2.38 m/s. What is the velocity of the coupled boxcars after collision? Take north as positive and express your result ...

### English

Please check for spelling and commas errors. If commas need to be placed somewhere please let me know where. Please let me know whether you want photographs taking of the altar during the ceremony or after the services. If you would prefer not to have pictures taking during ...

### English-Ms. Sue

Ms. Sue you know the description of the old house I did, well now I have to put all that into a paragraph. I want to make this paragraph seem really intersting and spooky. Ms. Sue could you please give me a spooky intro and conclusion for this, please. If not the conclusion ...

### Physics. PLEASE HELP!!

A small, spherical bead of mass 1.9 g is released from rest at t = 0 in a bottle of liquid shampoo. The differential equation of motion is dv/dt = g−b/m*v . The terminal speed is observed to be 1.6 cm/s. The acceleration of gravity is 9.8 m/s2 . Find the value of the ...

### Physics

A wheel is rolling ithout slipping at 487 meters per second to the right on a level surface. the diameter of the wheel is 100 centimeters. What is the angular speed of the wheel in revolutions per minute? Please walk me through your steps, don't just suggest a formula. Thank ...

### Intro to Physics

A sample of an unknown material appears to weigh 295 N in air and 165 N when immersed in alcohol of specific gravity 0.700. (a) What is the volume of the material? ___________m^3 (b) What is the density of the material? ____________ kg/m3 I am getting the wrong answer. Can you...

### PHYSICS HELP PLEASE!!

way safety engineers build soft barriers so that cars hitting them will slow down at a safe rate. A person wearing a safety belt can withstand an acceleration of 300 m/s 2 . How thick should barriers be to safely stop a car that hits the barriers at 81.7 km/h? Answer in units ...

### Physics check

A speeder traveling at 41 m/s passes a motorcycle policeman at rest at the side of the road. The policeman accelerates at 3.3 m/s2. To the nearest tenth of a second how long does it take the policeman to catch the speeder? Im sorry I am new to physics this is my first year and...

### physics

A person notices a mild shock if the current along a path through the thumb and index finger of one hand exceeds 80 ìA. In volts, calculate the maximum allowable potential for a hand with moist skin with a resistance of 67.7 kÙ. please help i am getting the wrong answer.why ...

### Physics :(( help please TT

Consider a five-pointed star made of resistors as shown below. Each resistor has resistance R=6 Ω. Find the equivalent resistance in Ohms between the points A and B. Details and assumptions Note: Points ABCDE are labeled for easy reference if you need to use some ...

### physics

The density of liquid carbon dioxide is about 0.8 g/cm^3. What volume fraction inside the fire extinguisher (when full) is occupied by CO2? The density of CO2 gas is negligible compared to the density of liquid CO2. My answer was 75%. Please verify. Thanks.

### Physics

A ball is thrown horizontally from a height of 16.01 m and hits the ground with a speed that is 5.0 times its initial speed. What was the initial speed? This question really boggles my brain. I have no idea how to solve this, given only the height. Could someone please steer ...

### physics!!

A skateboarder, starting from rest, rolls down a 14.0-m ramp. When she arrives at the bottom of the ramp her speed is 7.40 m/s. (a) Determine the magnitude of her acceleration, assumed to be constant. (b) If the ramp is inclined at 20.5° with respect to the ground, what is ...

### physics please help

The femur is a bone in the leg whose minimum cross-sectional area is about 3.60 10-4 m2. A compressional force in excess of 6.90 104 N will fracture this bone. (a) Find the maximum stress that this bone can withstand. (b) What is the strain that exists under a maximum-stress ...

### Physics please help!!

Piston 1 has a diameter of 0.524cm Piston 2 has a diameter of 5.64 cm. In the absence of friction, determine the force required on piston 1 necessary to support an object, m, with weight 1072 N. (Neglect the height difference between the bottom of the two pistons, and assume ...

### Physics Help Please

Suppose a 65-kg person can run 1000m in 5min. Assume that each stride is 1.5m long, and with each stride the runner must supply an amount of energy equal to her kinetic energy. How much energy (in food calories) is required to run 1km? Is your answer realistic?

### physics

a radiation survey meter observed gamma radiation of 150 mR/hr. The air field ionization chamber has a volume of 580 cubic cm. If the electron generated by the radiation in the chamber are swept out by an electric field, what is the current produced? please answer, thank you ...

### Physics

A 2.2-kg baseball is pitched to you at 21 m/s. You hit the ball back along the same path, and at the same speed. If the bat was in contact with the ball for 0.17 s, what is the magnitude of the average force the bat exerted on the ball? Please show all work and provide any ...

### Physics

A red ball is thrown straight up from the edge of the roof of the building. A green ball is dropped from the same point 1.80 seconds later.a)if the height is 60.0 m, what is u(red)?b)if u(red) greater than u(max) determine u(max). Ive solved abut i cannot understand b, please ...

### Physics atwood machine - please help!

On an atwood machine, which mass has a higher momentum - the hanging mass or the mass on the table? Thank you!

### grammar

please correct this sentence: the reason i A) WILL not be going to mexico is C)BECAUSE i will use up all my money D)IN ATTENDING an important meeting in singapore. E)NO ERROR i already know that the answer is c, but please explain. thank you.

### Chemistry- DRBOB!! PLEASE?

molecular orbital theory? my teacher was like "im not teaching it, but its going to be on your test" can you please summarize what it is, i read the online sites,tehy don't make sense...

### stat

please help!! pretty please!! i need to know how to this problem ASAP! suppose you pay $1.00 to roll a fair die with the understanding that you will get back $3.00 for rolling a 5 or a 1, nothing otherwise. what is your expected value?

### Algebra, check please?

5(N+2)=3/5(5+10n) And then I wrote down 5n+10 But what would do after that? I know that the equal sign basically cuts it inhalf so that it's two problems.. but I just don't know what to do from that point. Help please? -Allyson

### AP World History

3.Explain the major tenets of Hinduism and its evolution from the Aryans to the Gupta. Please help with this question I have no idea how to answer its the last one could you give me some websites please. -Thank You

### Algebra

I do not get this at all, please help me. I know we cannot post links, but I uploaded the picture of my homework here: ht tp: //img560 .imageshack. u s/ img5 60/994/hom eworkc.jpg DELETE THE SPACES PLEASE AND THANK YOU.

### science(please help)

Which of the following has the greatest effect on the formation of rain or snow? A)cloud cover C)air pressure B)humidity D)temperature My answer is C) am i right, if not please tell me what you got.

### English writing

Please ASAP can someone give me an introductory paragraph on the Truman show and the giver with the title and author and the thesis statement ? Please just an idea I need help

### English I Speech

Can anyone please share their idea of a strong, powerful hook, background information and thesis about fracking? Please this urgent. Be quick like your life depends on it.

### English

HI, I need help on a question I have read both books 50 times now what is the difference between Barrio boy and no gumption please help. And if your going to hate please don't state thanks!!!!

### social studies

how did You Chong, a Chinese bookkeeper for a grocer on Maunakea near Hotel St., contract plague ? please answer with your source(s) and maybe cite it please ? thank you very much tutors.

### Spanish

translate this to english please but do not use google tanslate because it is not accurate they don't give you good enough answers please help me as soon as possible thank you so much ms. sue! el parque nacional

### History please help!

Who were the first four caliphs? A)rulers who had a personal connection to Muhammad. B) a group of wealthy traders C) five gods D) missionaries to Africa I pick A. Please help!

### Physics problem

An object with a mass of 100kg is dropped from an 80 meter high building and leaves an impression in the ground of 15cm. A.What is the time needed to hit the ground? B. What is the speed of the object when it hits the ground? C. What is the coefficient of the friction between ...

### Physics problem

An object with a mass of 100kg is dropped from an 80 meter high building and leaves an impression in the ground of 15cm. A.What is the time needed to hit the ground? B. What is the speed of the object when it hits the ground? C. What is the coefficient of the friction between ...

### physics-rotational dynamics

Two astronauts, each having a mass of 75.0 kg, are connected by a 10.0 m rope of negligible mass. THey are isolated in space,orbiting their center of mass at speeds of 5.00 m/s. calculate A)magnitude of the angular momentum of the system by treating astronauts as particles and...

### Physics

Help with Physics homework Please and thank you!? I need help on these two questions. I'm not looking for the answer because I really need to learn how to do this on my own. But if someone could show me what equations to use to answer the steps in the questions and explain to ...

### Chemistry(Please help)

What is the pH of a 5.06E-2 M aqueous solution of sodium acetate? I know that I would set this up the same way I did for the previous question that I posted. I am just confused on how to find the Ka. I know it is kw/kb but for what compound is what I do not know. Chemistry(...

### english

Please help me with my thesis. i have to write a thesis statement in the topic topic "Poverty in USA". like i had lots but my teacher didn't agree with those. can anyone please give me idea what to write. by starting the sentence with " Poverty in USA ....." please give me ...

### physics

The x-component of vector A is -25.0 m and the y-component is +40.0 m. a) what is the magnitude of vector A? b) What is the angle between the direction of vector A and the positive direction of vector x? can you please help me with the steps to accomplishing these?

### Physics

What is the weight of an object whose mass is 50 slugs? What is the mass of an object whose weight is 50 lbs.? Please indicate formula used.

### physics

an unstretched hanging spring is 50cm long. suspending a 100N weight from it makes its lenght 60cm. Adding another 100N weight will make the spring -- 60cm, 70 cm, 80 cm, 100 cm, or 120 cm. No idea how they came up with any of the five ??? My answer was different! Please help!

### Physics

What is the probability density at the fifth carbon atom if the electron is in the n=2 energy level? I have the formula as follows: Probability density = p5= (2/1.65) sin^2 (4x2pi/11) I know the final answer is 0.69 nm -1. However, I do not know how to retrieve this final ...

### Physics. Please Help!!!

A hot air balloon starts at its launching station and it goes at a horizontal speed of 2.7 m/s and a vertical wind of 1.1 m/s. Once it reaches an altitude of 202 m, it stays at that altitude for 10.3 s, which is when it drops a sandbag. How far will the sandbag land from the ...

### Physics. Please Help!!

A hot air balloon starts at its launching station and it goes at a horizontal speed of 2.7 m/s and a vertical wind of 1.1 m/s. Once it reaches an altitude of 202 m, it stays at that altitude for 10.3 s, which is when it drops a sandbag. How far will the sandbag land from the ...

### Physics-Gravitation

What is the gravitational potential energy of a two-particle system with masses 5.4 kg and 5.0 kg, if they are separated by 1.3 m? If you triple the separation between the particles, how much work is done (b) by the gravitational force between the particles and (c) by you? ...

### Physics

While an elevator of mass 2681 kg moves upward, the tension in the cable is 29.4 kN. (a) What is the acceleration of the elevator? (b) If at some point in the motion the velocity of the elevator is 1.04 m/s upward, what is the elevator's velocity 3.96 s later? Please helppp ...

### physics. HELP PLEASE !

An athlete executing a long jump leaves the ground at a 28.0 angle and lands 7.60m away. part a)What was the takeoff speed? part b) If this speed were increased by just 8.0 % , how much longer would the jump be? i got for part a)9.48 m/s but i need help with part b

### Physics(Please help)

1) A force vector has a magnitude of 579 newtons and points at an angle 43o of below the positive x axis. Find the x scalar component and the y scalar component of the vector? For the x component I did 579cos(43) = 423.45 N. Is this correct? For the y component I did 579sin(43...

### Physics- PLEASE HELP

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

Photons of energy 12eV are incident on a metal. It is found that current flows from the metal until a stopping potential of 8.0V is applied. If the wavelength of the incident photons is doubled, what is the maximum kinetic energy of the ejected electrons? What is KEmax in eV. ...

### AP PHYSICS

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 help again!

A ball is thrown horizontally off a 35 m tall building. It hits the ground 80 m from the bottom of the tower. a. what is the balls time in the air [i got 2.67] b. what is its initial velocity? [i got 0] c. What is the magnitude and direction of its velocity as it strikes the ...

### Physics, Collisions

A pendulum of a given mass is pulled back through a given vertical height and released to swing back down to a 'wall' where it impacts. Can i use mg delta h to get E kin; and then use E= half mv^2 to get the collision impact velocity? Would someone check my thinking please? ...

### Physics

For beginner parachutists, the terminal velocity must be less than 5.00 m/s, and the parachutes used have a k-value that is normally distributed with a mean of 2.05/s and a standard deviation of 0.04/s. If the acceleration due to gravity is 9.81 m/s^2, determine the ...

### PHYSICS

2 pool balls of equal mass experience a perfectly elastic head on collision. 1 ball is traveling at 2m/s and the other at 3m/s in the opposite direction.What is thier speed just after impact? I know the balls swap speed and change direction but can't find the correct formula ...

### physics

A car is sitting at the top of an inclined plane, which is 5.2 meters long and meets the horizontal at an angle of 12 degrees. The cart is then allowed to roll to the bottom of the incline. What will be the velocity of the cart at the bottom of the incline. (4.61m/s) Please ...

### physics

Consider the following set of equations, where s, s0 and r have units of length, t has units of time, v has units of velocity, g and a have units of acceleration. Take k to be dimensionless.Identify if these are dimensionally correct or incorrect. 1)v^2= 2as + kav 2)s = s0 + ...

### Physics

An 80-ft-diameter Ferris wheel rotates once every 23s. What is the apparent weight of a 80kg passenger at the lowest point of the circle? Express your answer in SI units. I know to use the equation mg-N=m(v^(2)/r) but I can't figure out how to come away with the apparent ...

### Physics

A cricket ball rotates at 1800 rev/min as it travels through the space in a straight line at 160 km/hr. How many times does it revolve after traveling 20m? Can someone confirm with me if 13.5 revolutions in 20m is right. That's the answer i got too. If it's wrong can someone ...

### physics

PLEASE HELP! When Babe Ruth hit a homer over the 10 m -high right-field fence 80 m from home plate, roughly what was the minimum speed of the ball when it left the bat? Assume the ball was hit 1.2 m above the ground and its path initially made a 39 ∘ angle with the ground.

### Physics

Ive tried numerous methods, but I cant seem to get this right. Please help, and explain step by step. An object's position is given by x=bt+ct^3, where b=1.50m/s and c=0.640m/s3. To study the limiting process leading to the instantaneous velocity, calculate the object's ...

### Physics (Please Help)

At the He-Ne laser wavelength (L= 632.8 nm) the refractive indices of crystal quartz are n o = 1.54264 and n e = 1.55171 calculated from its Sellmeier equation. The laser is incident from the air onto the surface of crystal quartz at an angle of incidence of 45 degrees. For ...

### physics PLEASE HELP

A source emits sound uniformly in all directions. There are no reflections of the sound. At a distance r1 from the source the sound is 6.5 dB louder than it is at a distance r2 from the source. What is the ratio r1/r2?

### physics

a +35x10^-6 C point charge is placed 32 cm from an identical +32x10^-6 C charge. how much work would be required to move a +50.0x10^-6 C test charge from a point midway between them to a point 12 cm closer to either of the charges? please show work.

### Physics

True/False 1)Specular reflection obeys the laws of reflection while diffuse reflection does not. False. drwls said its true but I disagree can you please explain. 2)A convex lens is used to obtain an enlarged virtual image. True.

### math

On the first day he runs 1.5 km. Every day he runs 10% more than the day befor. a) Write down the distance he runs on the second day of training. ..... 1,5km +0,15 = 1,65 km b) Calculate the total distance He runs in the first seven days of training. When I counted my answer ...

### Physics Help!!!! Please check

A 3.00 kHz tone is being produced by a speaker with a diameter of 0.150 m. The air temperature changes from 0 to 29°C. Assuming air to be an ideal gas, find the change in the diffraction angle . Please tell me where I am going wrong. first I converted the temp to kelvin 0 = ...

### Physics

One of the most powerful cranes in the world, operating in Switzerland, can slowly raise a load of 6000 tonne to a height of 12 m. (1 tonne = 1000 kg) The acceleration of gravity is 9.81 m/s2 . How much work is done by the crane? Answer in units of MJ I found it by using Work...

### PHYSICS

Could u help with physics hw! i keep trying but i keep getting the wrong answer? a 71g autographed baseball slides off of a 1.3 m high table and strikes the floor a horizontal distance of .83m away from the table. 1.how fast was it rolling on the table before it fell off? ok ...

### Physics

Calculate the change in momentum in each of the following situations and state the direction of the change in momentum. a) A 4kg bowling ball strikes a stationary pin head-on at a speed of 3m/s. It continues to move in its original direction, but its speed is reduced to 2m/s. ...

### Physics

Calculate the change in momentum in each of the following situations and state the direction of the change in momentum. a) A 4kg bowling ball strikes a stationary pin head-on at a speed of 3m/s. It continues to move in its original direction, but its speed is reduced to 2m/s. ...

### Physics

I agree with this and see were it comes from net force = (delta p)/t so momentum is conserved when net force equals zero... net force = (delta p)/t 0 = (delta p)/t however the following is not true 0 = (delta p)/t = P - Po were p is momentum and Po is used to indicate inital ...

### Physics

Could someone please explain how you get this answer??? A skier with a mass of 60.0 kg pushes off with a horizontal speed of 3.0 m/s from the top of a snow covered hill. As he slides down the hill, his height decreases by 42 m over a distance of 100 m of travel. How much will ...

### English

Posted by rfvv on Thursday, December 16, 2010 at 3:40pm. Posted by rfvv on Thursday, December 16, 2010 at 3:21am. {At a restaursant} For hear or to go? Is this for here or to go? It's for here, please. It is to go, please. (Are the expressions above all grammatical? What is ...

### PHYSICS

A mass is thrown upwards with an initial velocity of 30m/s. A second mass is dropped from directly above, a height of 60m from the first mass 0.50s later. When do the masses meet and how hight is the point where they meet? I NEED TO KNOW HOW TO SHOW THIS IN A STEP BY STEP ...

### Physics

The frequency of circular motion for a charged particle moving around in the presence of a uniform magnetic field does not depend on ... a)The radius of the circle b)The mass of the particle c) The charge of the particle d) The magnitude of the magnetic field e) Actually, it ...

### PHYSICS- please help! i cant get my last problem

The compound eyes of bees and other insects are highly sensitive to light in the ultraviolet portion of the spectrum, specifically light with wavelengths between 300.0 nm and 400.0 nm. To what frequencies do these wavelengths correspond? (Assume that the speed of light to be 3...

### Physics

A shopper in a supermarket pushes a cart with a force of 35 N directed at an angle of 52(angle sign here) downward from the horizontal. Find the work done by the shopper on the cart as the shopper moves along a 50.0 m length of aisle. Someone tell me if this is right: W= (35....

### Physics-Please help with formula

If you were in a rotor style ride and the riders accelerate until the speed of ride is reached- if the radius of the cylinder is 5.0m and the coefficient of friction between clothes and wall is 0.5, how do you find minimum speed you would need to stick to the wall of the ride...

### physics

two ends of a train moving with constant acceleration pass a certain point with velocities u and v. what is the velocity with which the middle point of the train passes the same point? I have asked this question before you have answered u+v/2. but my mam says it is (u^2+v^2/2...

### Physics

For the first part of this question I got 12.12m/s B. With the help of a friend the boy measures the height to which the ball returns and finds it to be 5.2 meters. How fast was the ball moving when it left the ground? I wrote this down mass of ball: 0.40kg height if house: 7....

### physics

Two pieces of metal (A and B) are identical in every way, except that A has a much larger thermal expansion coefficient. If equal amounts of heat are added to both pieces of metal, which metal does more work on its surroundings? 1. A 2. B 3. They do the same work. 4. Unable to...

### physics

A bicyclist wants to make it from one building to the next. The first building he is standing on is 20 m tall. The building he wants to reach is 12 m tall. He is moving at 4 m/s and the gap between both buildings is 5 m. Will he make it? Please just show me how to break down ...

### physics please help

a 65 kg bag is dragged along a 12m ramp in order to get from the ground to the floor of the loading dock 2m above the ground. determine the efficiency of of the ramp. The frictional force acting on the bag is 50N due to the ramp. I don't understand how to the find the energy ...

### Math/physics

This is my last problem. Please help! A motorcycle rider starts out on top of a ramp 10 m high and then rides down and jumps the motorcycle when he comes to the end of the ramp (like evil knivel). The rider is at the peak of his jump at 5 m. How fast is the motorcycle going ...

### Physics

We have a heat engine that produces 150 J of heat, does 40 J of work, and emits 110 J into another system. What is the efficiency of the heat engine? Please don't give me the answer! Just help figure out how to find it! The description for the lesson with this question was 1 ...