What is Hill: Definition and 316 Discussions

Homework Statement The figure shows a cylinder of mass 3.5kg, radius 4.4cm and length 10.2cm with 105turns of wire wrapped around it lengthwise, so that the plane of the wire loop contains the axis of the cylinder. What is the least current which while flowing through the loop will prevent the...

Good Morning to evryboby. What is the power needed to climb a 20° slope with a 100Kg electric bike + 100Kg for the driver? Many thanks in advance. Regards to all. Rudy

https://scontent.fath3-2.fna.fbcdn.net/hphotos-xtf1/v/t1.0-0/s526x296/12804814_10208727068471849_3639991170291956856_n.jpg?oh=a60b7b49070602e57e99d4dfdf3545dd&oe=57640241 Yesterday my bf asked me to calculate the calories he burns to go up a hill. So of course the first thing I thought was to...

Homework Statement A 35-kg child goes down a hill on a 5-kg sled. Starting from rest, she reaches a speed of 30 km/h at the bottom of the hill. The hill makes an angle of 25 degrees with the horizontal. (a) Assuming there is no heat generated by friction and air resistance, how high is the...

Homework Statement A man (75kg) is sledding down a 20m high hill that is at an angle of 30 degrees. He is given a push that has him initially going 7m/s. He experiences a force of friction of 22N on his way down the hill. a) How much work is done by friction on his way down the hill? b) How...

If we have 2 Tanks connected with a siphon but the water in bigger tank is higher than the water in smaller tank, but the siphon goes from smaller tank over to the big tank and ends up at lower elevation than it started. Will the water flow in big tank like in the picture.

Homework Statement A cart travels up a hill at a constant velocity in 2.5 (s). What power is developed by the cart? m=120 kg meters=12m θ=21° Homework Equations P=w/t w=F(parallel)×meters×cosθ The Attempt at a Solution P= w/t= Fdcosθ/2.5= F(12)(.93)/2.5= 11,2F/2.5= 4.5F How do I find F?

Homework Statement Say you push a sled of mass m up a hill that is angled upwards at a certain angle \theta at a constant velocity. The hill has snow on it offering a friction force that is equal to 30% of the sleds weight. If you pushed the sled down the hill with the same amount of force...

Homework Statement Mountaineers are simulating a massive avalanche snowball by using a big Styrofoam ball (m = 75 kg; r = 1.50 m).They give it an initial impulse of 1500 kg m/sto start it rolling down the hill without slipping (no snow sticks to the ball, and ignore air resistance). Near the...

Homework Statement Alexander sled down a hill and on a snow-covered horizontal leveled ground. He wanted to calculate the highest velocity that the sled can reach. The hill is 3 meters high and 6 meters long. When Alexander sled down the hill he traveled 12,5 meters on the snow-covered ground...

Homework Statement We are trying to solve a problem where, we'll call him John, is being pushed down the hill too fast by Mary and when he goes back up the next hill he ends up flying up off the ground. We are trying to solve where, on the graph (coordinates) he lands. Here is what I know...

Homework Statement A marble that is rolling without slipping approaches a hill at 8.5 m/s. How high vertically will the marble go under these circumstances: If the hill is rough enough to prevent any slipping? If the hill is perfectly smooth? Why does the marble rise to different heights when...

Homework Statement Alice and Bob are having a competition to see who can throw a baseball the farthest from the top of a hill which slopes downward uniformly at an angle ϕ. Alice plays softball, and Bob doesn't have a particularly good arm, so he knows that he's probably going to lose...

Hello! I was accepted into UNC Chapel Hill, UMDCP, and UIUC for physics in the fall. Can anyone lend some insight on which program would give me the best chance for acceptance into graduate school or what the research opportunities are like at each university? I currently live in NC which makes...

Homework Statement A loaded truck has a mass of 3100 kg. The maximum speed it can maintain on a 5.0° hill is 80 km/h. What constant speed could the truck maintain on a hill with a slope of 10.0°? Assume the total force due to air resistance and friction is 700 N and that it does not vary with...

Considering getting a B.A in Physics with a concentration on energy at UNC- Chapel Hill. Any thoughts on possible careers? How marketable is this degree?

Homework Statement Two rollers, of masses 2kg and 3kg, are connected over a pulley by a massless string. They rest in equilibrium on two inclined slopes, as shown in the diagram to the left. Friction is negligible. What is the distance X? Homework Equations Fg = mg Component of Fg parallel to...

Homework Statement Consider a square hill barrier produced by a 10V potential. Incident upon this barrier is a steady stream of 5eV electrons. (a) If half the electrons are transmitted, how thick is the barrier? (Please derive the transmission probability rather than merely quoting it.)...

www.independent.co.uk/news/world/americas/should-a-man-with-an-iq-of-70-be-on-death-row-8503801.html He is no more breathing I read a list of countries sorted by number of death sentence: China, Iran, Iraq, Saudi Arabia, USA. Any comment?

So, I have a car I'm tuning using a road dyno software. This software basically uses the gear ratio of the car, it's total weight, and the speed it moves the RPM to determine it's power output (HP and Torque) In order to use this software a flat road is needed. That works well and is very...

Homework Statement A 900-kg car initially at rest rolls 50m down a hill inclined at an angle of 5.0^o. A 400-N effective friction force opposes its motion. (a) How fast is the car moving at the bottom? (b) What distance will it travel on a similar horizontal surface at the bottom of the hill...

Consider a 1200kg car cruising steadily on a road at 90km/h. Now the car starts to climb a hill that is sloped a 30 deg from horizontal . If the velocity of the car is to remain constant during climbing, determine the additional power required that must be delivered by the engine. KE=mv2/2...

Homework Statement The length of a slope is 500 meters and it's height is 10 meters. 60 kg sled went down the slope. Find the average friction force if it's speed in the end = 8 m/s (the starting speed = 0) Homework Equations Ft=mv-mv0 t=S/v The Attempt at a Solution Ft=mv-mv0=60*8=480...

find the energy of a required to accelerate a 1800kg car from 15 km/h to 75km/h an up hill road with a vertical rise of 55m KE=1/2m(V22-V12) KE=1/2(1800)(20.832-4.162) KE=1/2(1800)(433.88-17.30) KE=1/2(1800)(416.58) KE=1/2(749844) KE=374922 J I'm wondering if I'am on the right track, no...

Homework Statement Gayle runs at a speed of 4.20m/s and dives on a sled, which is initially at rest on the top of a frictionless snow-covered hill. After she has descended a vertical distance of 4.77m, her brother, who is initially at rest, hops on her back and together they continue down the...

Homework Statement A roller coaster car is going over the top of a 18-m- radius circular rise. At the top of the hill, the passengers "feel light," with an apparent weight only 60% of their true weight. How fast is the coaster moving? Homework Equations I think F=mv^2/ (r) F=ma The Attempt...

My problem goes : A projectile is fired with initial speed v_0 at an angle of \alpha up a hill slope \beta (\alpha > \beta) a) How far up the hill will the projectile land. Attempt to solution: I understood that this is a problem where I need to find the intersection of the parabola and the...

Homework Statement Suppose a can, after an initial kick, moves up along a smooth hill of ice. Make a statement concerning its acceleration. A) It will travel at constant velocity with zero acceleration. B) It will have a constant acceleration up the hill, but a different constant acceleration...

Just want to make sure If I have solved this question correctly. Homework Statement A 75 kg person walks to the top of a 240 m high hill expending 5.6 x 10^5 J of energy/ a. What was the potential energy of the person at the top of the hill? b. What is the efficiency of the person in walking...

Greetings, I'll be transferring to Chapel Hill in about a year for a double major in physics and math. I was curious if anyone on the Physics Forums had any experience or knowledge about Chapel hill in this specific area that may help me, or would at least be good to know. Thanks for the input...

Hi, I know this question has been posted before but could someone advise me if my answer for c) is accurate? I really want to make sure I understand how this works. The entire question is: "A child on a sled (m=47.0 kg) slides down a long hill starting from a rest position at a point 10.0 m...

Homework Statement A snowboarder goes down a ramp when initially at rest. The Total mechanical energy on top of the hill is 980 J and 400J at the bottom of the hill. Calculate efficiency of the ramp. Homework Equations Efficency = (Power out) over (Power in) The Attempt at a...

Hello PF, I am currently in an Analog Electronics course that comes with a lab. We use Art of Electronics (AoE) by Horowitz and Hill as our textbook, but after reading through it, I'm starting to feel that it's not as suited for a Physics course as it is for say, an Electrical Engineering...

Homework Statement I was tutoring the other day, when we came across a problem that had me stumped! A person standing on a hill that forms an angle \theta = 30^o wrt to the horizon, throws a stone at {\bf v} = 16 m/s up the hill at an angle \phi = 65^o wrt to the horizon. Find y_f...

In the sport of luge, a competitor slides on a sled down a 500-m long straight ice track inclined at 20o to the horizontal. Her initial speed is 2.0 m s-1. The coefficient of dynamic friction between the sled and the ice is 0.050. Neglect air resistance. What is her acceleration? What is her...

Homework Statement A 900 kg car is parked on a hill when its brakes fail. It begins to roll down the hill,which is at a 15 degree angle above the horizontal.The coefficient of rolling friction is 0.1. What is the car's speed after it has rolled 20m? Homework Equations F=ma v2=2aΔx...

Homework Statement A 900 kg car is parked on a hill when its brakes fail. It begins to roll down the hill, which is at a 15 degree angle above the horizontal. What is the car's speed after it has rolled 20m? Assum no friction. Homework Equations F=ma v2=2aΔx The Attempt at a Solution...

Suppose a man is climbing up a hill at angle 30 degree from the ground. The mass of the man is 50Kg and he climbs up the hill at uniform acceleration of 2m/s2. What is the work done in climbing up the hill and if he climbs down the hill at the same 30 degree angle with uniform acceleration of...

What work must be done to pull a loaded sleigh (total weight of 10 kg ) on the top height H=10 m. Gradient of slope amounts 30 degrees. Coefficient of friction between the sleigh and the ground decreases linearly along the way from 0,5 at the food of the hill to 0,1 in the top. The pararell...

Homework Statement An iceskater weighing 69kg is gliding up an incline hill at 20 degrees. How high up does the skater make it when her initial velocity is 8,9m/s and the friction between her skates and the ice is 0,97N. Homework Equations mg(y) = m*g*cos(20) mg(x) = m*g*sin(20) The Attempt...

Homework Statement http://puu.sh/5nLnI.png Homework Equations I = mr2 The Attempt at a Solution Moment of inertia: Mass density = mass / area = 2.59 / (π*9.52 - π*7.52) = 0.02424772368 kg / cm2I = (areaA)(density)(radiusA) - (areaB)(density)(radiusB) =...

[Solved] bottom of hill Homework Statement No friction, starts at rest. What is the force factor at the bottom of the circular loop? (see attachment) Homework Equations Conservation of Energy Equations The Attempt at a Solution EDIT: Solved below (incorrect solution was here)

Homework Statement Derive from Maxwell's equations these Hill equations for 's' and 'p' mode waves; s\hspace{3mm} modes: E(r,t) = \Psi_{s}(z)e^{i(\beta x - \omega t)}y \\ \hspace{10mm}Hill\, Equation for\, \Psi_{s}(z)\\ \hspace{17mm} \dfrac{d^{2}\Psi_{s}(z)}{dz^{2}} +...

Homework Statement Find the hill radius of Earth and calculate the velocity of an object falling from that radius (and from rest from the Earth's frame) at the point where it impacts the Earth. Relate this velocity to the escape velocity of Earth. Homework Equations Hill radius: r_h=R...

Homework Statement At the bottom of a hill, a box has a speed of 15 m/s. The hill forms an angle of 30 degrees with the horizontal. How far up the incline of the hill does the box slide?Homework Equations My answer: d = (vf2 + vi2) / 2a The Attempt at a Solution vi = 15 m/s vf = 0 m/s a =...

A bike rolling down a hill will on average stay upright for longer than a free standing bike? I can't think of a way to explain why this is?

Homework Statement A bicyclist coasts down a 7.0° hill at a steady speed of 5.0m/s. Assuming a total mass of 75kg (bicycle plus rider), what must be the cyclist's power output to climb the same hill at the same speed? Homework Equations EK=1/2 mv2 EG=mgh P=W/T The Attempt at a...

Homework Statement A boy stands at the peak of a hill which slopes downward uniformly at angle ##\phi##. At what angle ##\theta## from the horizontal should he throw a rock so that it has the greatest range? Homework Equations ##\mathbf{s} = \mathbf{v}_0 t + \frac{1}{2} \mathbf{a} t^2##...

Homework Statement Radius of loop: 20 m Mass of cart: 225 kg Gravity: 10 m/s/s (once I figure out how to do this I'll use 9.8 in the final project) Found so far: B) Velocity (top of loop) = 14.14 m/s C) GPE at the top of the loop = 90000 N C) KE top of loop = 22500 N D) KE (bot) =...

Homework Statement Suppose you are climbing a hill whose shape is given by the equation: z = 1400 − 0.005x^2 − 0.01y^2 where x, y, and z are measured in meters, and you are standing at a point with coordinates (120, 80, 1264). The positive x-axis points east and the positive y-axis points...