Newtons Definition and 494 Threads

Is it possible to hate Newtons Laws? Hi, I am taking a course in physics, and I have noticed that Newtons Laws, and Newtons Mechanics just bores me to death whenever I am reading about it or trying to do questions. On the other hand, we started to do some Energy and Work chapters, and the...

this is going to sound dumb, but here i go. through out my schooling i was preached " in a vaccum, a feather and a bowling ball would fall at the same rate". -thinking about the difference in theories with Aristotol, Galileo, and Newton, something didn't make sense to me. Talking about...

Homework Statement Imagine taking your dog for a walk. You feel a real bond for man's best friend. Could this be due to gravitational attraction? Estimate the force of gravity between you and your dog. Homework Equations force~mass1 x mass2 divided by distance^2 The Attempt at a...

Heres the problem http://img141.imageshack.us/img141/2820/49686394mt3.jpg Now I have to work it out using Newtons second law and Work energy... For Newtons second Law (F = ma)...would I be using I = mk^2 M = I\alpha than setting up F = ma...? and for work energy I am...

Homework Statement Check out my attachment to get an idea what is happening. What we have is an inclined plane with 2 masses (m1 and m2) which are touching one another and the angle of the incline is 30 degrees. The coefficient of kinetic friction between m1 and the plane is 0.23 = mu_k1...

Joe was driving on the highway a car ahead of him was driving far below the speed limit so he decided to pass. In the first second he gained(gained means to get nearer to something you are chasing) 5m on the car and as he accelerated he gained 1.5 times as much distance in each second as he had...

Hi guys. This is my first post. I am currently on an engineering apprenticeship and its mostly practical but i have been given a Newtons law question which i am finding very hard. I have attempted it but still come up stuck. I have attached the question with the drawing. I have...

For some odd reason, I'm having no problems with the rest of the exercises, though this one is really annoying as i just can't seem to get it right. Here's a picture of the exercise h t t p://img2.freeimagehosting.net/image.php?4bc2e12442.jpg...

I was thinking about Newtons law and come across something interesting. F=ma=GMm/r^2 therefore a=GM/r^2. This is the acceleration of the satellite towards the larger mass. But this acceleration is only accurate assuming that the larger mass is stationary. But f=Ma=GMm/r^2, so there is an...

Homework Statement What is the ratio of the gravitationalpull of the sun on the moon to that of the Earth on the moon?(Assume the distance of the moon from the suncan be approximated by the distance of the Earth from the sun.) Homework Equations F_{g} =...

Im trying to find my work when climbing up stairs. If I convert my weight into Newtons, do I still need to multiply it by 9.8? Since i weigh 135, I multiplied that by 4.5 to get my weight in Newtons. I then multiplied that by 9.8, after that I multiplied that by 3.0 m ( the distance of the...

Newtons law, interacting objects question?? A block of mass 5.00 Kg sits on top of a second block of mass 15.0 Kg, which in turn sits on a horizontal table. The coefficients of friction between the two blocks are : μs = 0.300 and μk = 0.100. The coefficients of friction between the lower...

can someone please help to reason out this. because i am confused...is the question about static friction..please help On a truck which is moving straightforward on an horizontal road there is a big cube of concrete of mass m. The mass of the truck is M. The truck brakes suddenly with an...

Hey guys, was just wondering if you could explain the answer to this question. So basically we have a picture of a book resting on a table. On this book there is the weight force downwards and the reaction force upwards, both acting on the center of mass. The question: A class of students is...

Homework Statement three blocks attatched by cords that loop over frictionless pulleys. Block B lies on frictionless table, block a hangs off the left side of the table, while block c hangs off the right side. mass a= 6kg mass b= 8kg and mass c= 10kg. When the blocks are released, what is the...

[b]1. A figure shows an overhead view of a lemon half and two of the three horizontal forces that act on it as it is on a frictionless table. Force F1 has a magnitude of 4.70 N (in the negative x and positive y direction) and is at θ 1 = 29°. Force F2 has a magnitude of 7.00 N (in the positive x...

Homework Statement The equation dQ/dt = k ( T - Troom) is Newtons law of cooling. dQ/dT being the rate of heat loss. I want to convert this equation to dT/dt, the rate of temperature decay. How do i go about doing this? Homework Equations The Attempt at a Solution Is Q...

A red box and a blue box sit on a horizontal, frictionless surface. When horizontal force F is applied to the red box, it accelerates 4.88 m/s2. a) If F is applied to the blue box, it accelerates at 1.32 m/s2. What is the ratio of the masses of the boxes (mass of the red box/mass of the blue...

A rope is tied to a 97.8 kg log. When you pull on the rope with a horizontal force of magnitude 706 N, the log moves at constant speed. a) Find the magnitude of the resistive (frictional) force acting on the log. You may assume the frictional forces acting on the log is constant. N b)...

I have this problem on a web assignment due on the 20th of this month. A few of the problems have completely blown my mind including the following: A force F0 causes an acceleration of 18 m/s2 when it acts on an object of mass m sliding on a frictionless surface. Find the magnitude of the...

Homework Statement A block A (mass 2.25k) rests on a tabletop. It is connected by a horizontal cord passomg over a light, frictionless pulley to a hanging block B (mass 1.3kg). The coeffisient of kinetic friction between block A and the tabletop is 0.45. After the block is released from the...

I'm reading section 17 of Mathematical Physics by Donald H. Menzel on Harmonic functions. They start with Newtons law of gravitation (although the following method can be aplied to any potential field with a 1/r dependence.) see...

Homework Statement You are dragging a stack of shoeboxes along the floor by a rope (an odd situation I must say). If the total mass of the shoeboxes is 18kg and the rope is pulled at an angle of 45 degrees with no acceleration i) what is N (normal force)? and ii) What is the tension of...

Hey guys, I was just wondering if you could help me with a question that has been bugging me for a while now. I've thought of many possibilities to the answer yet i still can't find the right one. The question is that, when a fly strikes the windshield of a truck moving at let's say 60km/h, why...

a 20 kg box is on frictionless surface acted on by two horizontal surfaces. when in same direction, it pulls 11 m/s but in opposite directions, it pulls only 1 m/s. determine magnitude of each force. answer: 120 N , 100 N okay...i need help with this. i am using Newtons law: force=mass x...

Homework Statement Ok this is kind of long. This is the 4th question on my homework assignment and I need to give background on the first 3 to make sure I got those correct. 1. I am sure on this since it was simply finding the weight of a rocket ship that has an intial mass of 3kg. Answer is...

Hey all, I am new to Physics. Recently changed majors from technical writing to physics for the amount of interest I have in the subject. I have been doing ok but I missed a couple of questions on my last homework and I feel that I should have had somebody check my general solved statements...

hi, I am not really sure where this belongs, and being a complete noob at physics, i was just enquiring if someone could inform em of the formula to calculate the distance an object weighing 80kg would need to fall in order to be effected by 4,400 Newtons?

My teacher asked us too prove that Hamiltons principle proves that Newtons equations of motion hold for N particles. I'm not sure that i fully grasp the concept but this is my understanding so far: Using the lagrangian we can prove Newtons law for specific situations, however Hamiltons...

I have spent a ton of time researching my question but i can't find the answer i know that for every action there is an equal and opposite reaction i know if you have a tire on the ground and when it starts spinning it pushes so that the concret will go the other way but the ground it to...

proof of Newtons gravitational law!? hi every one, i am new in this forum n here is my first question that really bothers me for a long time we always take for granted the formula given by Newton F=G*(M1*M2)/R^2 do u have any proof that is really satisfing.n i don't understand why Earth is on...

It says that every reaction there is a opposite and equal reaction. Why do things still move if everything is opposite and equal?

http://img75.imageshack.us/img75/9735/prob1ve7.jpg Frictionless surface, pulled along a horizontal line, string has no mass Calculate the mass m The answer says 17,1 kg, i don't know if it is correct, can sum1 please give a solution with the steps:smile:

Homework Statement A plank, of length L = 3.7 m and mass M = 7.0 kg, rests on the ground and on a frictionless roller at the top of a wall of height h = 1.70 m (see the figure). The center of gravity of the plank is at its center. The plank remains in equilibrium for any value of θ >= 74° but...

given mass= 100kg and it's a freely falling body. so what is the force in Newtons??

If I have a small model car and use a spring scale to measure the force, my reading is .130 kg. How do convert that to Newtons? Is gravity relevant to this equation? I know that F = m x a the mass of the car is .387 kg is the accerleration the acceleration of the car or gravity?

hey dudes i read in a book that when an electric current flow that the electrons move preety slow [maybe 1mm/s I'm not sure] now i also know electricity travels at the speed of light (ideally) so that an electron c*1s away will take 1s to start moving after i close the circuit so i was...

Homework Statement Two spherical asteroids have the same radius R. Asteroid 1 has mass M and asteroid 2 has mass 2.58·M. The two asteroids are released from rest with distance 12.35·R between their centers. What is the speed of second asteroid just before they collide? Give answer in units...

Please help me because my teacher has not explained how to do questions involving angles. Blocks X and Y of masses mx=5.12kg and my=3.22kg are connected by a fishing line passing over a frictionless pulley. Show that block X slides up the incline (35.7 degrees above the horizontal) with...

A bicycle of bicyclist of combined masss 62 kg go over a hump of radius 6m at a speed of 5m/s. what is their combined appararent weight at the top of the hump? is it just... Fc = MAc Fc =M(V^2/r) Fc = 62(25/6) Fc = 290N

(1) What is the magnitude of the net force on a skydiver in N when an 810 N gravitational force and a 750N force of air resistance act on him? Fn = 810 Fg = 750 810 - 750 = Fm 60N (2) A 1200 kg car is moving in a staright line at a constant speed of 15m/s when the brakes are...

Homework Statement 1) The coefficient of kinetic friction for a 22-kg bobsled on a track is 0.10. What force is required to push it down at a 6.0 degree incline and achieve a speed of 60 km/h at the end of 75 m? 2) A box is given a push so that it slides across the floor. How far will it go...

Question: Just give me hint of free body diagram where force will be considered because I have to find the force.I have tried this problem with past rules but now al little force problem so the question is Question: A man weights 180lb;the plateform and attached frictionless pully weigh a total...

Newtons second law problem, show all work including units Question: How much horizontal net force is required to accelerate a 1000 kg car at 2 m/s^2?I am not sure which formula to use in this equation

Homework Statement Find the readings on each of the balances in these 4 situations (strings are massless and incline is frictionless): (sorry about the photo - don't know how to fix it) Homework Equations F=ma, W=mg The Attempt at a Solution 1) Seems easy enough. I am...

[SOLVED] Newtons Laws Questions Question: A 3 kg block moves up a 40 degrees incline with constant speed under the action of a 26-N force up and parallel to the incline. What magnitude force must act up and parallel to the incline for the block to move down the incline at constant velocity...

Homework Statement You are conducting an experiment inside an elevator that can move in a vertical shaft. A load is hung vertically from the ceiling on a string. The tension in the string is measured to be 10% less than the weight of the load. No other forces are acting on the load. Which of...

You have a bucket filled with water. A spring has been soldered to the bottom of the bucket, and a cork is attached to the other end of the spring. The cork is suspended motionless under the surface of the water. You are standing on a stationary elevator holding the bucket. The elevator then...

Homework Statement An object weighing 5.0 Newtons displaces a certain volume of water when dropped into a large beaker of water. The weight of the displaced water is 3.5 Newtons. The object is free to sink or float. What would be the value of the bouyant force is another object twice the...

acc to Newtons gravitational theory f=GmM/r^2 and the distance r is taken from the centre of mass of the object so hypothetically if there was a flat rectangular planet gravity would be highest at the centre of the rectangular planet and if we stand away from the center gravitational pull...