Hill Definition and 313 Threads

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...

Homework Statement This is not a homework question per se but rather something I was thinking about while driving the other day. I am in a car on a hill with constant slope traveling at an initial speed. How can I come up with a set of equations describing both velocity as a function...

3rd time I'm posting in a day. Homework Statement A skier (68 kg) starts from rest but then begins to move downhill with a net force of 92 N for 8.2 s. The hill levels out for 3.5 s. On this part of the hill, the net force on the skier is 22 N [backwards]. T/I (a) Calculate the...

Hi, i am confused with where to start with. A cyclist is on a bicycle with a mass of 10kg rolls down a hill 150m high. with zero losses what is the velocity of the bike at the bottom of the hill? could some one please send me in the right direction with formulas

1. A small hockey puck slides without friction over the icy hill shown in the figure and lands 6.2m from the foot of the cliff with no air resistance. What was the speed v0 at the bottom of the hill? There is also a diagram showing the hill. The puck starts at the bottom and travels 15.3m to the...

I was wondering if a spacecraft (or any other object) could 'co-orbit' the Earth by orbiting the Sun beyond our Hill sphere. For example, could this object 'hover over' the North (or South) Pole at >1,500,000 km? Thanks in advance!

Hello. I have got one interesting question for you. Imagine that you are driving a car down the hill. What is the speed to the most warmed brakes? Today I thought about it and I wonder how it somehow calculate numerically but I don't know how. Have you got any ideas?

Homework Statement There are two objects rolling down a hill of incline theta, one is a sphere and one is a disk, each of equal radius and mass. Which one gets down first and how much faster than the other? What's the coefficient of static friction of the hill? Homework Equations Moment...

Homework Statement A tow truck driver hooks up a car to tow it up the hill. The car weighs 1500kg. the cable makes an angle of28 degrees with ground. the cables tension is 1900 N . the static coefficitient is 0.5 and the acceleration is at 6/m s^2 . what is the frictional force on the car...

Homework Statement Given the following key, find two plaintext pairs that encrypt to the same ciphertext. \begin{pmatrix} 9 & 5 \\ 7 & 3 \\ \end{pmatrix} (mod \ 26) Homework Equations The Attempt at a Solution Let the two plaintext pairs be (a, b) and (c, d). Let the...

Alright so I have a question on the work done with constant acceleration up a hill. I was working an example problem that asked for the work a hiker must do on a 15.0 kg backback to carry it up a hill of height h = 10.0m with the hiker keeping a constant velocity...

Homework Statement Two solid spheres -- a large, massive sphere and a small sphere with low mass -- are rolled down a hill. Which one reaches the bottom of the hill first? Homework Equations ICM= (2/5)MR2 The Attempt at a Solution I thought that this would be the smaller sphere...

Max. speed you can drive on a circular hill an still be in "Uniform Circular Motion" Homework Statement The top of a hill is in the shape of a circle of radius 25 meters. Homework Equations a) What is the normal force that the road exerts on an 1800kg car as it tops the hill with a...

Homework Statement I have a hill with a roller coaster cart on it and it goes down and around a loop-the-loop the radius of the loop is 10m Diameter=20m What is the minimum speed the cart needs to go to keep it on the track? There is no friction, what is the height of the hill...

A cyclist has a speed of 5 m/s when she beings to coast down a hill, as shown in the figure. At the bottom of the hill, her speed has increased to 12m/s. the mass of the cyclist plus bicycle is 75kg. a) Calculate the work done by gravity on the cyclist and bicycle. b) Calculate the...

Homework Statement A 1550-kg car experiences a combined force of air resistance and friction that has the same magnitude whether the car goes up or down a hill at 21 m/s. Going up a hill, the car's engine produces 44 hp more power to sustain the constant velocity than it does going down the...

Homework Statement A skier starts from rest at the top of a hill. The skier coasts down the hill and up a second hill,The crest of the second hill is circular, with a radius of r = 38.5m. Neglect friction and air resistance. What must be the height h of the first hill so that the skier just...

Homework Statement A 61.2kg skier coasts up a snow-covered hill that makes an angle of 25.2o with the horizontal. The initial speed of the skier is 8.34m/s. After coasting a distance of 1.97m up the slope, the speed of the skier is 3.43m/s. Calculate the work done by the kinetic frictional...

My Son asked me a question, I am not sure how to answer it. It feels easier to push or roll a heavy ball up a hill than it is to pick it up and carry it up the same hill. The ball has the same potential energy at the top of the hill no matter how it got there so it would appear to be...

Three children, Aaron (20kg), Beth (25kg) and Charlie (30kg) take off on sleds at the top of a hill. Who will reach the bottom first? (μ=.15) a)Aaron b)Beth c)Charlie d)All of them reach at the same time f=μN The answer is d. my first guess was A because i thought that since Aaron...

Homework Statement A San Francisco cable car loses its brakes and runs down a hill 30.4 m high. Calculate the velocity of the car at the bottom of the hill. Homework Equations Height = 30.4 m Time = ? Acceleration due to Gravity = 9.8 m/s2 Initial Velocity = 0 m/s Final Velocity = ...

Homework Statement A house is built on the top of a hill with a nearby 45° slope (Fig. 6-19). An engineering study indicates that the slope angle should be reduced because the top layers of soil along the slope might slip past the lower layers. If the static coefficient of friction between two...

Homework Statement A Bus drives 1km up a hill in 5.0 minutes. It then drives down the hill in 4.0 minutes. For the bus, find a) the average speed up the hill b) the average speed down the hill c)the average speed for the whole trip d)why is the answer for c) not equal to (speed up the hill +...

Homework Statement What power must a man of mass 85 kg have to bicycle 850m up a hill, inclined at 5.2° to the horizontal, at a constant speed of 15.6m/s? The force of friction on the man and the bicycle is 175N parallel to the incline.Homework Equations The Attempt at a Solution m= 85kg...

A disk with mass m and radius R is rolling down a hill with no slipping, until it reaches a wall and then stops: I want to write a set of equations describing the position cordinates x and y of the disk's center of mass (point A) and the cordinates for point B. mgsin(theta)=ma ->...

Homework Statement A block slides down a hill. The hill has a gentle 20° slope with respect to the horizontal. The block has an initial speed of 6 m/s. If the block comes to a stop after traveling a total distance of 11 m along the slope, what is the coefficient of kinetic friction between the...

Homework Statement A sports car is accelerating at a rate of 4.23m/s^2 up a 14 degree hill. If there are dice hanging from its rear-view mirror, what angle will they swing on? Homework Equations ƩF = ma Kinematic Equations The Attempt at a Solution Well, I'm thinking that I need to...

Homework Statement A car of mass m is traveling along a circular hill of radius r with a constant speed v, write an expression for the force "on the car from the hill" when the car is at the top of the hillHomework Equations F (weight) = mg F (centripetal) = mv^2 /rThe Attempt at a Solution I...

Homework Statement A projectile is fired with speed v0 at an angle θ from the horizontal as shown in the figure (see attachment). Homework Equations A. Find the highest point in the trajectory, H. Express the highest point in terms of the magnitude of the acceleration due to gravity g, the...

I'm trying to understand a problem someone gave me recently. there is a frictionless track that initially starts flat then there is an incline of 20 degrees then it levels out again at the bottom of the incline. you have two masses, 1 is .4 kg and is located at the top of the hill and has an...

Homework Statement A car traveling at 24.0m/s runs out of gas while traveling up a 20.0degree slope. How far up the hill will it coast before starting to roll back down? Homework Equations Vf^2=Vi^2-2a(g*sin(20)(Xf-X0) The Attempt at a Solution I don't know if that is correct...

Homework Statement A solid ball is released from rest and slides down a hillside that slopes downward at an angle 69.0 degrees from the horizontal. What minimum value must the coefficient of static friction between the hill and ball surfaces have for no slipping to occur? Homework Equations...

Homework Statement A rope attached to a 19.0kg wood sled pulls the sled up a 22.0 degree snow-covered hill. A 11.0 kg wood box rides on top of the sled. Homework Equations I have no what the equation may be, I was just doing some research and came across this website plus others and...

Homework Statement A skier starts from rest at the top of a large hemispherical hill. Neglect friction and show that the skier will leave the hill becoming airborne at a distance of h=R/3 below the top of the hill. R is the radius of the hemispherical hill. Homework Equations...

Homework Statement My first-year college engineering design class was tasked with building a vehicle that can make it up a ramp of 5' in length that is at a 45 degree angle. At the top of the ramp is a 2' flat platform. The ramp (both the ramp itself and the platform at the top) is covered...

Homework Statement A sled with your physics teacher, having a combined mass of 125 kg, travels over a perfectly smooth icy hill.The hill is 11.0 m high and at the bottom of the hill, the sled is moving at 22.5 m/s. The center of a puddle, which is 0.60 m in diameter and covered in a thin layer...

Homework Statement "A bicyclist can coast down a 5° hill at a constant 7.0 km/h. Assume the force of friction (air resistance) is proportional to the speed v so that Fair = cv." (a) Calculate the value of the constant c. (b) Calculate the average force that must be applied in order to...

Homework Statement A 2.8kg block slides over a smooth icy hill. The top of the hill is horizontal and 70m higher than its base. The 70m plateau is 80m from the base of the hill. What is the minimum speed the block must have so that it will not fall into the pit on the far side of the hill...

Homework Statement A car is sliding down an icy hill inclined at 1.6 degrees, find the coefficient of friction. Homework Equations f_k=\mu_k*n The Attempt at a Solution Don't know how to begin it only given the angle of the hill.

Homework Statement The first box slides down a hill and gains speed and ends at v=1 \dfrac{m}{s}. The second box has an initial speed of v_{0}=1 \dfrac{m}{s} and slides down the same hill. What speed does it end up with? The boxes have equal masses. Solve this without first solving...

Consider a cyclist going up an inclined plane. Will going in a zigzag path make it easier for the cyclist to go up the hill? (Assume that there IS friction on the incline)

Homework Statement A 50kg skier skis directly down a frictionless slope angled 16* to the horizontal. Assume the skier moves at a negative x direction. A wind force with component Fx acts on the skier. What is Fx if the skier's velocity magnitude is constant? Homework Equations...

Hi, Can someone please solve this question for me, including step by step instructions ? I can solve the ones where the mass of a car is given, but can't do this one. Homework Statement Setting off from rest the car accelerates uniformly and climbs a steep hill which has a gradient of 1...

Homework Statement A 10kg Box is being pushed up a 3m long hill at the angle of 30 degrees. A constant force is being applied to the box parallel to the ramp. The box starts from rest. For questions a and b we can assume no friction. a) If you were to get the box to the top of the hill in...

Just something I started to wonder about. It is said that if you park on a hill, put the hand brake on and leave the car in gear. First when I heard about it, I figured its pretty clever, giving the wheels more friction to overcome. Now shortly after I heard that when parking on a hill, facing...

Homework Statement What power must a man of mass 85 kg have to bicycle 850m up a hill, inclined at 5.2 degrees to the horizontal, at a constant speed of 15.6 m/s? The force of friction on the man and the bicycle is 175N parallel to the incline. m = 85 kg d = 850m dy = 850m * sin5.2 v =...

Homework Statement http://img822.imageshack.us/img822/5347/byccc.jpg A bicycle rider starts his motion from the top of the hill A at an initial velocity (Vo). From that point, the bicycle roll freely (without using pedals) in a the circular path. A) Calculate the speed of the rider at...

Hi! A block with mass 35 kg is pushed upward with a horizontal force of 400N along a slope at an angle of 30 °. The block makes a displacement of 2 meters, where it's speed changes from 1m/s to 1,8m/s. What is the Coefficients Of Friction? 1) 0.312 2) 1.099 3) 0.039 4) 1.31...

Homework Statement I have solved the following question in two ways which give different answers. Both methods are similar but a little bit different so I think one is wrong. Can anyone advise me which (if either) of the answers is right? A stuntman is preparing his next stunt. He needs...

Hello everyone! I am new here, so I am not sure how things normally work. anyways, on the the problem. I have a ramp made out of channeling, approximately 8 foot long, that i am going to roll spherical objects down. i want to find out the theoretical time it will take. friction doesn't...