126,957 results, page 14

### Physics

A helicopter is ascending vertically with a speed of 5.20 m/s. AT the height of 125m above the earth, a package is dropped from a window.How much time does it take for the package to reach the ground. ****Note: Please show the steps.

### physics

hey, if someone could please help me solve this: object kicked at 45 degree and travels 82 m b4 hitting the ground. what was its vo? how long was it in the air? how high did it go? tell me if this is right, i got 740m for the height... doesnt sound right..

### physics (making a yo-yo)

I am required to make a yo-yo that will unwind at a slowest rate possible, without using friction as a factor. Will it help if I make it hollow, so it would have more rotational inertia? Any other ideas? Please help!!

### physics

calculate the image position and magnification for an object 3cm tall laced in front of mirror with a focal length of 12cm, if the object is placed at 2f... I got: di: 24cm and m=-1 please tell me if this is right.. thank you so much :)

### Physics

Please help ! Finish the following statement: "The greater the number of lines on a diffraction grating of a given size," a)the greater b)smaller then a)the range of wavelengths that can be diffracted b)the distance between the bright fringes produced

### Physics (Projectile Motion)

Please reply to this one urgently: Horizontally moving plane at 600kmph speed, at a height of 1960km, drops a package at point A and it drop at point B. Find the distance between A and B.

### Physics

A person walks 3.0847x10^1 m East, then turns around and walks 8.677x10^0 m West. The total time to walk this distance was 7.8624x10^2 s. What is the speed of the walker, expressed to 3 significant figures? please help me im so confused

### Physics Help Please :(

Projectile Motion A rifle is fired horizontally and travels 200m East. The rifle barrel is 1.90m from the ground. What speed must the bullet have been traveling at? Ignore Friction.

### physics

A convex mirror has a focal length of 19.0 cm. Determine the object location for which the image will be one-fourth as tall as the object. i know that 1/f=1/do=1/di. when i put the numbers into the equation i keep getting 23.75 and its saying that its wrong. can you please ...

### physics

A flowerpot falls from a window sill 37.6 m above the sidewalk. What is the velocity of the flowerpot when it strikes the ground? The acceleration of gravity is 9.81 m/s2. Answer in units of m/s Please show me the formula and steps i would use to solve this, Thanks!

You are walking at 4.40 km per hour across a frozen lake in the snow. You do not realize that with each step you turn 0.40 degrees to your right. If your step length is 58.0 cm what is the diameter, in meters, of the circle that you are inadvertently tracing out?

A skier of mass 71 kg is pulled up a slope by a motor-driven cable. The acceleration of gravity is 9.8 m/s2. How much work is required to pull him 64.6 m up a 33.8 slope (assumed to be frictionless) at a constant speed of 2.53 m/s? Answer in units of kJ

A 5-kg ball is thrown straight up in the air with an initial speed of 24m/s. After its release and before it hits the ground when is the ball in free fall? My answer is at all times. Is this correct? Thank you.

There is a diagram of a ball being thrown in a horizontal diection at 30m/s and there is an angle of 48degrees and a side with 4m. How long is the ball in the air? I am confused because I am not sure of the equation. I know that is is something like y = yo + ? - 1/2gt^2 Thank ...

### Physics

The liquid in the tube has a density of 1.48 g/cm^3 . The atmospheric pressure is 1.013 X 10^5 newtons per square meter. What is the pressure P in the container? Please walk me through your steps, don't just suggest a formula. Thank you very much.

### Physics(Please check, thanks)

A football player kicks a ball with a speed of 25m/s at an angle of 40 degrees relative to the horizontal. Ignore air resistance. 1) What is the ball's range? R= V0^2 sin Q / g Is this the correct equation to use?

### Physics

How many newtons of force are necessary to accelerate a 0.0050 kg mass at the acceleration (a) of 9.81 m/s2 with the force expressed in the correct number of significant figures? (F = ma) 0.04905 N 0.049 N 0.05 N 4.91 × 102 N Please help me :( It's just one little question.

### Physics

For safety in climbing, a mountaineer uses a nylon rope that is 55 m long and 0.9 cm in diameter. When supporting a 82-kg climber, the rope elongates 2.0 m. Find its Young's modulus. I got 34737.433 but that is not the right answer please help!

### Physics

A 60 W light bulb at 120 V is left on in your house to prevent burglary, and the power charges 10 cents per kilowatt-hour, how much will it cost to leave the bulb on for 30 days? Please show how to work this

### physics

An aeroplane flying at 350km/h in a direction of N 40 degrees E strike a wind blowing from N 50 degrees W at 75km/h calculate the resulting velocity of the aircraft? need help trying to work this out. please. any help would be great.

### Physics

A meteorite weighing 1860N strikes the earth with a velocity of 45.2m/s. What is its kinetic energy? Write in SN to one decimal place. When I plugged in (1/2)(1860N)(45.2m/s)^2, I got the answer 1.9e6, but it was incorrect. Please help. I'm really confused!

### physics

Choose one of the Laws of Thermodynamics (zeroth, first, second, or third) and give a brief summary of its development. Who is credited with "discovering" it and when? How did the four laws come to be ordered as they are? Please explain in detail

### physics

Please, anyone help me please. Q: An object is placed 17.8 cm from a first converging lens of focal length 13 cm. A second converging lens with focal length 24 cm is placed 10 cm to the right of the first converging lens. (Take the direction to the right to be positive.) (a) ...

A .30kg softball had a velocity of 15m/s at an angle of 35 degrees below the horizontal just before making contact with the bat. What is the magnitude of the change in momentum of the ball while it is in contact with the bat if the ball leaves the bat with a velocity of a)20m/...

### MATH

Harriet needs to ship a small vase. The box she will use has a volume of 216 cubic inches. If the side lengths are all the same, what is the length of each side of the box? Hint: V = S^3 PLEASE ANSWER NICE AND NEAT AND CORRECT PLEASE AND THANK YOU!! =) :-) AND EXPLAIN IT GOOD...

The drawing shows a collision between two pucks on an air-hockey table. Puck A has a mass of 0.030 kg and is moving along the x axis with a velocity of +5.5 m/s. It makes a collision with puck B, which has a mass of 0.055 kg and is initially at rest. The collision is not head-...

### math

Saying that 4<(sq.root of x)<9 is equivalent to saying what about x ? a. 0<x<5 b. 0<x<65 c. 2<x<3 d. 4<x<9 e. 16<x<81 Please help. Does this problem relate to 'x'values on the xy coordinate system ? If so please explain the concept here. If ...

### Science (Please Respond SOON!)

I think I'm using the wrong formulas or SOMETHING... Here's the question: "Two equal charges are separated by 3.7 ´ 10^-10 m. The force between the charges has a magnitude of 2.37 ´ 10^-3 N. What is the magnitude of q on the charges?" Here's my work: F = kc(q1q2/r^2) 2.37 x ...

### Physics help please!

A cylindrical metal can with a radius of 4.25 cm is floating upright in water. A rock is placed in the can, causing it to sink 0.0230 m deeper into the water. What is the weight of the rock?

Can you help me with this question, too? Suppose that the boat is supposed to arrive at a point directly across the river from its starting point. a) What should be the heading of the boat?

### physics uncertainty

experiment times: .15, .13, .16, .14, .15, .14, .15, .14 so i found the average to be .15 and the highest value was .16 the lowest value was .13 so what is the uncertainty? (in other words... .15 plus or minus what number?) please explain. thanks

### physics help!!

a plane moving horizontally at 120 m/s drops a package from an elevation of 240 m. How far did the package go before it hit the ground? Step by step directions please!

### physics

please help: A repelling force occurs between two charged objects when the charges are of a. unlike signs b. like signs c. equal magnitude d. unequal magnitude

### physics

You exert a force of 455N in pulling 15.0m of rope using a pulley system to lift a 935N object 5.0m. What is the efficiency of the pulley system? Please help, I appreciate it a lot.

### Physics

What is the difference between magnetic field of a bar magnet anf the magnetic field around a current-carrying coil? Please answer with a good explanation.

### physics

A fisherman's scale stretches 3.5 cm when a 2.1 kg fish hangs from it. I know that k=590 N/m and f=2.7 Hz. How do I find the amplitude of vibration if the fish is pulled down 3.2 cm more and released so that it vibrates up and down? Please help!

### physics

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

a golf ball is launched at a 37 degree angle from the horizontal at an initial velocity of 48.6 m/s. state the initial velocity in rectangular coordinates. please show me how to figure this out

A ball bounces to 45 percent of its original height. What fraction of its mechanical energy is lost each time it bounces? What is the coefficient of restitution of the ball-floor system?

A ball bounces to 45 percent of its original height. What fraction of its mechanical energy is lost each time it bounces? What is the coefficient of restitution of the ball-floor system?

A football is kicked with a speed of 18 m/s at an angle of 65° to the horizontal. How long is the football in the air? Neglect air resistance Would I use the equation y=y0 + voy t -1/2gt^2 ?

### Physics

A 14.0 kg bucket is lowered vertically by a rope in which there is 181 N of tension at a given instant. What is the acceleration of the bucket? May someone please walk me through this problem step by step. Thank you

A system does 210 J of work on its environment and gains 80.6 J of heat in the process. Find the change in the internal energy of (a) the system and (b) the environment. I am not sure how to start this.

A system does 210 J of work on its environment and gains 80.6 J of heat in the process. Find the change in the internal energy of (a) the system and (b) the environment. I am not sure how to start this. Thank you for the help.

### Physics

Help me please I'm stuck on this question 2.In a thunderstorm at 20.0°C, Karen sees a bolt of lightning and hears the thunderclap 3.00 s later. How far from Karen did the lightning strike? Show your work.

### Science (Physics)

Two resistors 3ohms and 6ohms are connected in parallel across a 6V battery, what is the current flow through the 3ohms resistors? Just the formula please.

### Chemistry

Can someone please tell me what to expect from Beginner High School chemistry? Is it mostly applying mathematics like physics? Or basically memorizing like biology? Thank you!

### physics

a projectile with a horizontal component of 13m/s and a vertical component of 18 m/s would have an overall velocity of m/s??? at and angle of ?? above the horizontal. Can you please help me fill in the two blanks thank you

### Physics

An object is thrown vertically upward and has a speed of 12 m/s when it reaches one fifth of its maximum height above the launch point. Determine its maximum height. g=9.81 m/s^2. Please help

### Physics

An object is thrown vertically upward and has a speed of 12 m/s when it reaches one fifth of its maximum height above the launch point. Determine its maximum height. g=9.81 m/s^2. Please help

### physics

the tires of a certain car begin to lose their grip on the pavement at acceleration of 5 m/s to the power of 2 if the car has this acceleration , how many seconds does it required reaching a speed of 25 m/s starting from 10 m/s?. Please help me

### physics

Mrs. Johnson's kid is trying to drink with a straw that runs through an airtight cork in the top of a bottle of water. Please explain to her kid why he won't get any water.

### physics

Mrs. Johnson's kid is trying to drink with a straw that runs through an airtight cork in the top of a bottle of water. Please explain to her kid why he won't get any water.

### Physics

An aircraft travels 250 km on a heading of 330 degrees. It then turns due east and travels 420 km. How far and on what heading did it end up from it's starting point? Please help!!!

### college

Select the properly punctuated sentence. a. Please let me know; when I may contact you. b. Please let me know, when I may contact you. c. Please let me know when I may contact you.

Out of 42 kids in a class twice as many failed Ela as math,4 failed both. If 7 failed neither, find how many failed each subject. Please help and show work it would be great thanks i really need help thanks

A daredevil is riding a motorcycle on the inside of a spherical metal cage of radius 9.7 meters. The total mass of the person and motorcycle is 79.2 kg. If he is to make a vertical circle within the cage at some constant speed, v, what normal force, in Newtons, does he feel at...

### PHYSICS!!!!! HELP!

The velocity of a diver just before hitting the water is -8.6 m/s, where the minus sign indicates that her motion is directly downward. What is her displacement during the last 0.86 s of the dive? im so stuck. i tried this problem several times, and my answers werent correct. ...

How much work is done by the centripetal force (in this case, the friction between the tires and the road) on a 1200 kg car moving on a circular track of radius 50 meters at a constant speed of 31.4 m/s? A. 7.4 • 10^6 J B. 19.7 J <--- C. 2136.7 J D. 117,600 J E. 0 J

### vy? in Physics

During what time interval does vy become zero? So I can't really understand what vy means, I know its a abbreviation but I need help on this problem that has a cannon shooting a cannonball horizontally and it has 3 points; the first being 1s, then 2s, then 3s which is when the...

### physics Q

can you please help me with this please. thank you. A small mass m hangs at rest from a vertical rope of length l that is fixed to the ceiling. A force then pushes on the mass, perpendicular to the taut rope at all times, until the rope is oriented at an angle delta and the ...

### Physics

A dog that can swim at 1.0 m/s jumps in a river that is flowing 3.0 m/s at an angle of N60*E. Solve the resultant velocity vector of the dog if he heads north. What direction is the dog acutally heading? can someone please help thanks

### physics.....help me please....

1) A 1.0 kg mass is attached to the end of a vertical ideal spring with a force constant of 400 N/m. The mass is set in simple harmonic motion with an amplitude of 10 cm. What is the speed of the 1.0 kg mass at the equilibrium position?

### physics

given that the mass of an electron is 9.1 x 10^-28 grams and the charge on an electron is 1.6 x 10^-19 Coulombs, calculate the voltage required to lift an electron 5 cm. the question was previously answered, but I did'nt understand it .. could some show me again please.

A charge rod is brought near a pile of tiny plastic sphere. Some of the spheres are attracted to the rod, but as they touch the rod, they are flung into different directions. Explain. Thanks :)

### Physics

Suppose you put a 100 W light bulb in a container of water and use it to heat the water. How long would it take to raise the temperature of a gallon of water at 25 C to 90C? Please explain!

### physics

For a football player bending the ball around a defensive wall, state three principles which govern the flight path of the ball and the amount of spin imparted on to the ball? (3 marks) please help?

### PHYSICS

A BOATMAN ROWS TO A PLACE 48KM DISTANT AND BACK IN 14 HOURS; HE FINDS HE CAN ROW 4KM WITH THE STREAM IN THE SAME TIME AS 3KM AGAINST THE STREAM. FIND THE RATE OF THE STREAM? please help me :(

### physics

Hi! I have a problem for physics homework and I though I knew how to solve it but apparently it is wrong, please help! 'Two cars, one of mass 1000 kg, and the second of mass 2400 kg, are moving at right angles to each other when they collide and stick together. The initial ...

### math- quick help!

The area of the smallest (shaded) square measures 1 square unit. What is the area of the largest square? (there are 7 squares) Please, please, please help me!!!

I just cannot seem to be able to grasp the concept of solving polynomial inequalities. Can someone please explain, step by step, how to solve them? Here's a problem I can't solve. Please use this as an example: (x-2)(x-5)<0 I cannot thank you enough for helping me with this...

### Geometric Constructions HELP!

Congruency means that two figures or items are exactly the same size and shape. Where in life would it be vitally important for two or more items to be congruent? Can you give me ideas or examples about: the with wings of an airplane and tires of a car. Please! Please! Please!

A suitcase of weight mg = 450 is being pulled by a small strap across a level floor. The coefficient of kinetic friction between the suitcase and the floor =0.640 a) Find the optimal angle of the strap above the horizontal. (The optimal angle minimizes the force necessary to ...

A monitor displays the graph y = 3 sin 5x. What will be the amplitude after a dilation of 2? I am so confused.....can somebody please help me.... please??? I know the graoh of sin x but what is dilation? can somebody please explain????

### Physics (please check)

Please let me know if my answers are not correct/not thorough enough. 1) Q:What happens when the number of loops in the armature of a generator is increased? 1) A:More loops= more voltage _________________________ 2) Q: Why does a piece of iron behave like a temporary magnet ...

### English

Hey, I need your suggestions on this one. Could you please name some of the most beautiful, most emotional pieces of writing you've ever read. It can be poetry or prose or titles of novels or even someting you've written yourself, if your gonna do that can you please give me a...

### English

Can you please check the sentences? Thank you, Writeacher. 1) Are there any questions before you start? Did you have any difficulty in doing your homework? 2) Take a photocopy and pass the others on. Share these copies, one between two. Please, keep an eye on time. 3) Let's go...

If you have 4 points on a plane you can join them all with non-crossing paths, its possible. But if you try 5 points it seems like you cant do it. Prove that it doesn't work using Euler's equation. There's 5 vertices, 9 edges and 6 faces.

### PHYSICS

Suppose that a tank contains 680m^3 of neon at an absolute pressure of 1.01*10^5 Pa. The temperature is changed from 293.2 to 294.3 K. What is the increase in the internal energy of the neon? I don't have any idea to do it. Please help! Give me some ideas!THANKS A LOT!!!!

### Physics

There is a charge that is 1uC and another charge that is 2 uC. They are 10 cm apart. I need to find a point where the electric field is zero. All I have is this kq1\a=kq2\(10-a)^2 where q1=1 where q2=2 where k=9*10^9 I am lost after this I know I use regular algebra but i don'...

### physics

How long would it take for the Earth to complete a full turn if a person at 27° northern geographical latitude floats apparently weightlessly across the room? Use REarth = 6,379 km for the radius of Earth. Help me please!

### Physics

A 200 g mass attached to a horizontal spring oscillates at a frequency of 2 Hz. At one instant the mass is at x=5 cm and has a Vx=-30 cm/s.Determine: a) the period ( i got T=.5s) b) the amplitude c) the max speed d) the total energy need equations to solve this, please help.

### physics

Discharging Capacitor For R = 1000 W, C = 2000 mF, Qo= 20 mC. (a)How long will it take before the capacitor discharges to Qo/100. (b)What is the value of current at t = 4 sec. I am completely lost on how to solve this question, please can anyone give me help in the right ...

### physics

a car starting from rest is accelerated at 2m/s(square) for 10s, then moves at constant velocity for 20s and then decelerates at 1m/s(square), finally stops. how far does it travel during its trip? please help me! I need in solution for that problem

### college physics

A point (labelled P in the figure) is attached to the rim of a disk of radius 0.2 m, which can turn around an axis through its center. It is rotating counterclockwise with a speed of 2.5 m/s. Can someone please help me solve this equation step by step?

### college physics

A swimmer is heading straight for the other shore of a river with a velocity of vs=0.7 m/s relative to the water, but is carried away by the current, which has a velocity of vr=0.3 m/s. It takes her 20.3 s to get across. How far downstream does she end up? Can someone please ...

### physics

A projectile was fired at 35 degrees above the horizontal. At the highest point in its trajectory its speed was 200 m/s. If air resistance is ignored, the initial velocity had a horizontal component of 0. How is this possible? Someone explain it for me please. ty

### Physics

A mass m is traveling at an initial speed of v0 = 25.0 m/s. It is brought to rest in a distance of 62.5 m by a force of 15.0 N. The mass is? Could you just enlighten me on what formula to use please.... little lost although I think the answer is 37.5kg am I anywhere close?

### Physics

A sprinter can accelerate with constant acceleration for 2.70 s before reaching top speed. He can run the 100-meter dash in 10 s. What is his speed as he crosses the finish line? Please show me all the steps to solving this problem. Thanks

### physics urgent

A 1.5 m tall man stands 2 m in front of a flat wall mirror. Please find: image distance and height of image I have the formulas but i don't know how to solve this without the focal point or a radius...pls help!!!!!!!

### physics Important please

A potential difference of 12.0V is maintained across an electrical device with a resistance of 10.0Ω. What total charge passes through a cross section of wire attached to this device over a period of 4.00s?

### Physics

If the distance between the spheres is halved,how will this affect the magnitude of the force? And also this other question here:what does the fact that the force is repulsive tell you about the charges?...PLEASE HELP,MY TEACHER WILL PUNISH ME IF I DON'T DO TSHIS HOMEWORK.

### PHYSICS NEED HELP ASAP

A car traveling 16.0m/s crates into concrete embankment and steps in 0.08s. Calculate: the initial speed in mi/hr the average acceleration of the car during the collision in m/s^2 Please show all work than you

### NEED HELP ASAP PHYSICS

A car traveling 16.0m/s crashes into concrete embankment and stops in 0.08s. Calculate: the initial speed in mi/hr the average acceleration of the car during the collision in m/s^2 Please show all work than you

### physics

Sally the bug has an initial speed of 20.0cm/s. She then accelerates at 8.00cm/s^2 for 5.00s. calculate sallys total displacement? which i did and got 200 cm Displacement during the 5th second? can you please help and show all work

### Physics Check My Work Please

A 8 kg block is moving with an initial speed of 6 m/s on a rough horizontal surface. If the force is 12 N, approximately how far does the block travel before it stops? *I have: V^2=Vi^2+2ax 0=(6 m/s)^2 + 2(-9.8 m/s^2)(x) -36 m^2/s^2 = -19.6 m/s^2(x) x = 1.83 m. *Is this ...

### Please Check: College Physics

A 8 kg block is moving with an initial speed of 6 m/s on a rough horizontal surface. If the force is 12 N, approximately how far does the block travel before it stops? *I have: V^2=Vi^2+2ax 0=(6 m/s)^2 + 2(-9.8 m/s^2)(x) -36 m^2/s^2 = -19.6 m/s^2(x) x = 1.83 m. *Is this ...

### Physics Problems

Can you please help me with the following problem? Two charges separated by one meter exert 1-N forces on each other. If the charges are pushed to 1/4 meter separation, the force on each charge will be?

### Physics

The launching speed of a certain projectile is 6.4 times the speed it has at its maximum height. Calculate the elevation angle at launching. I have noo idea how to start this one. Please help!

### physics

how do i solve for this..? please write out the equation for me to understand..:) an elevator weighing 2.00 * 10^5 N is supported by a steel cable. what is the tension in the cable when the elevator is accelerated upward at a rate of 3.00 m/s^2? (g=9.81 m/s^2) thanks a lot!