Newtons Definition and 494 Threads

Homework Statement A ball of mass M is suspended by a thin string (of negligible mass) from the ceiling of an elevator. The vertical motion of the elevator as it travels up and down is described in the statements below. Indicate for each of the situations described the relation between value...

A plane which is flying at constant speed v, and a height h, above the sea, must drop a bundle of supplies to a castaway of a small raft. a) write down Newtons second law for the bundle as it falls from the plane, assuming you can neglect air resistance. Solve your equation to give the...

if r, v, a denote the position, velocity, and acceleration of a particle, prove that d/dt [a . (v x r)] = d/dt(a) . (v x r ) (the periods between a and (vxr) denotes a dot product, and the actual question shows a dot over the a instead of d/dt(a) I know the point is that you get v x...

Homework Statement 1) A block is affected by three forces, and I have found the direction and magnitude of the resulting force, and thus the direction and magnitude of the acceleration. I know that the magnitude of the velocity vector for t = 5 is 4.7 m/s and that the distance traveled for t...

Why do we accept Newtons laws? For every action, there is an equal and opposite reaction. why? An object in motion tends to stay in motion. Why does it need a force to stop it?

The question: assuming that the moon circles the Earth in an orbit of radius d show thatthe periodic time T of the moon may be expressed as: T=2pi d sqrt d/r sqrt g where r is the radius of Earth and g is acceleration due to gravity on Earth's surface i took up physics 2 to 3 months ago on...

Homework Statement F=ma can be written as F=ma(along x, y or z-direction, ) when applying this equation along say horizontal x direction, the direction of acceleration needs to be taken as it is a vector. i mean say 2 forces of 5 N and 3 N are applied on a 2 kg body that moves towards...

Homework Statement An astronaut of mass(m) is a certain distance between two planets where his net force=0. What is the ratio of the masses of the planets? Homework Equations F=\frac{Gm_{1}m_{2}}{r^2}\vec{r} The Attempt at a Solution Well if one planet has more mass than the other...

Newtons laws...examples I need to explain and illustrate examples of each of Newtons laws. They have to be different then all of the regular examples. ex. leaning against a wall. Any examples for me? And technical explination please

Three charges are fixed to an xy coordinate system. A charge of +14 uC is on the y-axis at y= +3 m. A charge of -14 uC is at the origin. Lastly a charge of +47 is on the x-axis at x= +3 m. Determine the magnitude and direction of the net electrostatic force on the charge at x= +3 m. Specify...

:confused: Homework Statement A chair of mass 13.0 is sitting on the horizontal floor; the floor is not frictionless. You push on the chair with a force = 45.0 that is directed at an angle of 40.0 below the horizontal and the chair slides along the floor. [b]2. Homework Equations...

Homework Statement Two blocks are lined up in a row. Block A a mass of 1kg, and Block B with a mass of 2kg. If block a is A is pushed forward by 12N, how much force does Block B exert on Block A. Friction can be nelected. Homework Equations Newtons Third law F(A on B)=-F(B on A)...

Homework Statement hi there, really don't know how to attempt this, could someone please give guidance, thanks. a crane needs a force of 3kN to lift a mass of 6 tonne. if the load is initially at rest and the maximum velocity is 5m/s, determine the time taken to lift the load. Any help would...

Hello! We often have lots of free time on our hands at work when we should be er... working, anyway we use this time to debate questions that none of us are qualified to answer in a 'I'm 110% right B***H' way. So I decided to come here and post a couple of the ones we have been arguing in the...

(1)An elevator is being lifted up and elevator shaft at a constant speed by a steel cable. All frictional effects are negligible. In this situation, forces on the elevator are such that? 1. the upward force by the cable is greater than the downward force of gravity. 2. the upward force by...

1. Two blocks are connected by a rope that passes over a set of pulleys. One block has a weight of 412N, and the other has a weight of 908N. The rope and the pulleys are massless and there is no friction. a.) What is the acceleration of the lighter block? b.) Suppose that the heavier block is...

A duck has a mass of 2.9 kg. As the duck paddles, a force of 0.11 N acts on it in a direction due east. In addition, the current of the water exerts a force of 0.19 N in a direction of 57° south of east. When these forces begin to act, the velocity of the duck is 0.13 m/s in a direction due...

im stuck with this problem: the question asked for the gravatational force of attraction between moon and Earth while the moon's radius is not given. do i need the moon's radius? since r is the distance from the center of moon to the center of Earth (right?) and the second question of the same...

please help me to finding out the value of X for forward difference Newtons formula i am tryign since 2 weeks but i fails where the values of arguments are a1, a1+h, a1+2h, a1+3h and there cross ponding values are p,q,r,s respectively

Homework Statement If one ball of a Newtons cradle is released at any velocity, why can't two balls on the other side be moved with half of the velocity of that ball. Homework Equations Law of consrvation of Energy and Low of conservation of Momentum The Attempt at a Solution Don't...

Hello, I have a question with a simple Tension - Mass problem. Here is the question: For the systems in Equilibrium, find the unknown tensions and masses. a) http://answerboard.cramster.com/answer-board/image/ed663c5fcb01e8fb6c7522cf963b49f1.jpg b)...

[b]1. When the hot water in a certain upstairs bathroom is turned on, a series of 18 "ticks" is heard as the copper hot-water pipe slowly heats up and increases in length. The pipe runs vertically from the hot-water heater in the basement, through a hole in the floor 5 m above the water heater...

I have a problem where I have an air cooled condensing unit located in a large room within a building. The volume of the room is approximately 27,195 cubic feet. The air cooled condensing unit rejects 102,600 btu/hr to the space. Assuming the ambient air temperature of the space is 95 degrees...

so I was helping my friend today and ran into a problem. the problem was to use Newtons method to approx. the intersection points of two graphs. f=x^2 g=cosx so I subtracted f-g, found the derivative and pluged in some guesses. Except all of my guesses just blew upwards in values...

Newton's THIRD law: implications on kinetic energy edit: after thinking about it a little more, I realized something. After having landed, my kinetic energy becomes what it began as (practically zero). nvm then.

i need help with this problem please help (If you use a horizontal force of 30.0 N to slide a 12.0kg wooden crate across a floor at a constant velocity, what is the coefficient of kinetic friction between the crate and the floor?) PLZ HELP AHHHHH ITS DUE TMRW SO PLZ HELP

Hello, the question I'm having trouble with is: "A 8.00kg block of ice, released from rest at the top of a 1.5 m long frictionless ramp, slides downhill, reaching a speed of 2.5 m/s at the bottom. What is the angle between the ramp and the horizontal?" My first attempt to solve this...

Piston 1 has a diameter of 0.34 in. Piston 2 has a diameter of 1.0 in. In the absence of friction, determine the force, necessary to support the 500 lb weight over piston 2. I used F(1) = pi(r1^2)/pi(r2^2)*F(2) and got the wrong answer. I used radii of .17in and .5in. Is that the right...

I got this problem as part of a long homework packet, was able to figure out all the problems but the last 3, so here is one of them, but i don't have a book. I really have no idea on how to approach this problem, so i was hoping someone could lead me through it and help me figure it out... I...

I have to apply the 3rd law i think to this, just not sure how to. A 2000 kg motorboat's propeller pushes on the water toward the west with a 2000 N force. The wind blowing toward the south pushes the motorboat with a 500 N force. Determine the location of the motorboat 10 seconds from the...

Can you please help me out with this problem?!? Suppose that a 1000 kg car is traveling at 25 m/s (about 55 mph). It brakes can apply a force of 5000 N. What is the minimum distance required for the car to stop. :confused:

A block is propelled up a 48 degree frictionless inclined plane with an initial velocity of 1.20 m/s...A) how far up the plane does the block go before coming to a rest. B) How long does it take to move to that position? for part A) , i have initial velocity and I am looking for x...

Problem : A car is to tow a 2,270kg truck with a rope. How strong should the rope be so that it will not break when accelerating the truck from rest to 3.00 m/s in 12.0 seconds? So I assume it wants me to find the tension?...but the 12 seconds is throwing me off...I'm not sure what that...

I was just wondering if anyone knew how to comvert Newtons to pounds. If anyone knows it would be greatly appreciated. Thanks

I am needing help on a few problems that I have to do for class. If anyone could help on any of them that would be great. 1)Bob, who has a mass of 75 kg, can throw a 500 g rock with a speed of 30 m/s. The distance through which his hand moves as he accelerates the rock forward from rest until...

I really need help with this question. I've tried solving it but i just can't do it. The question A loaded dump-truck having a total mass of 2.4*10power of 4 kg is traveling east at 85km/h.The truck driver can apply a braking force of 5.5*10 power of 4 to the wheels without causing the...

Sorry people, not sure where I am going wrong, I am just not sure in which direction to take this question. I don't even know where to start. A box with mass of 22kg is at rest on a ramp inclined at 45 degrees to the horizontal. The coeffecient of friction between the box and ramp are (Static...

http://img.photobucket.com/albums/v638/ravenatic20/cablecars.jpg Like my MS Paint skills? haha The image shows a section of an alpine cable-car system. The maximum permissible mass of each car with occupants is 2800 kg. The cars, riding on a support cable, are pulled by a second cable...

Luggage is transported from one location to another in an airport by a conveyor belt. At a certain location, the belt moves down an incline that makes an angle of 2.5 degrees with the horizontal. Assume that with such a slight angle there is no slipping of the luggage. Determine the magnitude...

A 28.0 kg block is connected to an empty 1.00 kg bucket by a cord running over a frictionless pulley. The coefficient of static friction between the table and the block is 0.45 and the coefficient of kinetic friction between the table and the block is 0.320. Sand is gradually added to the bucket...

Hi I have a problem I need someone to check over and see if I have it right! Thank you for trying in advance Responding to an alarm, a 92kg fireman slides down a pole to the ground floor, 3.2m below. The fireman starts at rest and lands with a speed of 4.9 m/s. Find the average force...

I have 2 questions that I am approaching, one seems very simple but I am still at a loss. The other I have attempted multiple times to no avail. Here they are: 1. An arrow, starting from rest, leaves the bow with a speed of 28.9 m/s. If the average force exerted on the arrow by the bow was...

The heaviest invertebrate is the giant squid, which can have a weight of about 1.5 (imperial) tons spread out over its length of 64 feet. What is its weight in Newtons? I tried converting the tons to kilograms and multiplying by 9.8 but didn't get the right answer. Where should the 64 feet...

Is acceleration involving N just N/kg? so If I have a ball that is 7kg and 5 N of force is applied will the acceleration be 5 / 7 = 0.71 m/s/s ?

At the local grocery store, you push a 15.2 kg shopping cart. You stop for a moment to add a bag of dog food to your cart. With a force of 12.0 N, you accelerate the cart from rest through a distance of 2.24 m in 3.00 s. What was the mass of the dog food? F=ma m=f/a I rearranged...

hello everyone, Im new to this forum but i really need some help doing a physics assignment. I am trying to use Newtons second law and the equation for wind resistance(click link) to determine the the angle made by a specific velocity. The link to the assignment is...

Very sorry, but I just don't know.. If there is a 5kg load on an object, let's say a book on a table.. what is it's force in kgN? Is it 5kg x 9.8?!

The Deligne Dam on the Cayley River is built so that the wall facing the water is shaped like the region above the curve y=0.1x^2 and below the line y=180 . (Here, distances are measured in meters.) The water level can be assumed to be at the top of the dam. Find the force (in Newtons) exerted...

Newtons 3rd law+Horse Cart System+Action/Reacton..help needed ASAP! im a sophmore in the ib program and I'm in conceptual physics i have a test tommorow on Newtons third law and all the stuff that goes along with it.. so i need an answer on this pronto! first of all.. if you are standing...

I have this one problem dealing with Newton's law of cooling: \frac{{dT}}{{dt}} = - k(T - A) I'm basically trying to determine at what time someone died! The info I have is that at time of death, the temperature was 98.6 degrees, at 10 AM it was at 92 degrees, and at 2PM it was at 86 degrees...