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A 50-kg sled is pulled 20 meters over ice at a constant speed. What is the frictional force? How much work is done?

A 50-kg sled is pulled 20 meters over ice at a constant speed. The coefficient of friction between the sled and the ice is 0.13. A) What is the frictional force? B) How much work is done in pulling the sled 20 meters?

Heat and Thermodynamics: Work done in a cycle

Please explain problem in word or pdf format closed path with 4 processes 1st process Isochoric V= 2m^3 P-initial = 3x10^4 Pa P-final = 8x10^4 Pa 2nd process Isobaric V-initial = 2m^3 V-final= 5m^3 P = 8x10^4 3rd process Isochoric V= 5m^3 Pi =8x10^4 Pa Pf =3x10^4 Pa 4th process Isobaric Vi = 5m^3

Speed, Work, Earth Clock and Direction of Motion

See attached file for full problem description.

Mathematical Methods in the Physical Sciences

Find the general Solution of each of the following differential equations. y^1 + xy = sin x (x^2)(y^11) + 2xy^1 + y = x^2

Energy Content of Gasoline

Could use some help with this problem and solve using a traditional physics formula: Assume the energy content of gasoline is 40 MJ per liter. How many kilometers will a car go if its engine is 25% efficient and it encounters an average retarding force of 1000N at highway speed?

Forces: Gravity, Friction, Constant

19. An 80N crate slides with constant speed a distance of 5.0m downward along a rough slope that makes an angle of 30 degrees with the horizontal. The work done by the force of gravity is: A. -400J B. -200J C. -69J D. 200J E. 400J 20. A man pulls a sled along a rough horizontal surface by applying a constant force F

Initial Momentum of the Ball

A pitcher throws a slow ball straight across the plate at 40.0 m/s. The batter hits the 0.200 kg ball straight back at 60.0 m/s. If the bat is in contact with the ball for 0.500s, a) What is the initial momentum of the ball? b) What is the final momentum of the ball? c) What is the change in momentum of the ball? d

Using the Work-Energy Theorem

Pushing a Cat. Your cat "Ms." (mass 7.00 kg) is trying to make it to the top of a frictionless ramp 2.00 m long and inclined upward at 30.0 degree above the horizontal. Since the poor cat can't get any traction on the ramp, you push her up the entire length of the ramp by exerting a constant 100-N force parallel to the ramp.

Calculating Work and Kinetic Energy

(See attached file for full problem description) --- Consider the system shown in the figure. The rope and pulley have negligible mass, and the pulley is frictionless. The coefficient of kinetic friction between the 8.00-kg block and the tabletop is . The blocks are released from rest. Use energy methods to calcula

Work required to move electric charges to infinity

A rectangular box has three charges at the corners with the length of the box being x = 0.55 m and height y = 0.36 m. How much work must be done to move the three charges; -3.3 µC, -6.1 µC, and +2.7 µC infinitely far from one another?

What is the velocity of the proton just before it hits the negative plate?

Please see the attached file for full problem description. 5. Two metal plates are held at a potential difference of 40 volts, in a vacuum. A proton is released near the positive plate, and moves toward the negative plate under the influence of the electric field. A proton's mass is 1.67 * 10^-27 kg. (A) Just before the pr

Work and Energy: Car, Gasoline, Air Conditioning, and Baseball

Section 1. Jim owns a car. Does his car use more gasoline when its lights are on? When the air conditioner is on? (Note: The battery does not run these devices while the engine is running.) Explain. Section 2. Sally wants to measure how much work she did during her throw of a baseball. How?

Electric Potential Energy of a Solid Charged Sphere

Calculate the electric potential energy of a solid sphere of uniform charge density rho; total charge Q and radius a using dU = dq(Vf - Vi). See attached file for full problem description with proper symbols.

Set of Problems on Hydrostatics

Please solve problems 13, 14, 15, 18 and 22 in the attachment.

Basic Physic Questions

Question 1: A 3.0-g bullet traveling at 350 m/s hits a tree and slows down uniformly to a stop while penetrating a distance of 12 cm into the tree's trunk. What was the force exerted on the bullet in bringing it to rest? Question 2: A big car of mass 2m travels at speed v, and a small car of mass m travels with a speed 2v. Bo

Friction: Uniform Internal Temperature

An iron plate is held against an iron wheel so that a sliding frictional force of 50 N acts between the two pieces of metal. The relative speed at which the two surfaces slide over each other is 40 m/s. A) Calculate the rate at which mechanical energy is converted to internal energy. B) The plate and the wheel have masses of 5.0

Work Power Energy: Conservation of Mechanical energy

A ski jumper leaves the jump ramp with an initial speed of 28.1 m/s and a height (relative to the bottom of the ski hill) of 46.2 meters. She encounters -6627 Joules of work due to air resistance during her flight through the air. Determine the speed (in m/s) of her 45.2-kg body the instant prior to striking the ground at the bo

Calculating car engine efficiency in gasoline burn

The burning of gasoline in a car releases about 2.85à?104 kcal per gallon. If a car averages 42.9 km/gallon when driving 86.2 km/hr, which requires 24.9 hp, what is the efficiency (in percent) of the engine under those conditions?

Work per second by engine

A 4-cylinder gasoline engine has an efficiency of 0.230 and delivers 205 J of work per cycle per cylinder. When the engine fires at 23.3 cycles per second, what is the work done per second?

Kinetic Energy and Radiation with Electrons

Radiation of a certain wavelength causes electrons with a maximum kinetic energy of 0.62 eV to be ejected from a metal whose work function is 2.65 eV. What will be the maximum kinetic energy (in eV) with which this same radiation ejects electrons from another metal whose work function is 2.01 eV? Units are in eV.

Rotational Motion: Equations for rotational motion

A wheel that is rotating at 33.3 rad/s is given an angular acceleration of 2.15 rad/s/s. Through what angle has the wheel turned when its angular speed reaches 72.0 rad/s?

Energy Loss/Speed

Take g= 9.8ms(-2) Please answer all questions with full explanations thank you A cyclist starting from rest freewheels for 200m down a slope of 1 in 10 (sin0 = 0.1) If the mass of the cycle and rider is 75kg: 1) What is the loss of potential energy of the cycle+rider? 2) If the speed of the cycle at the bottom of the h

Forces, Fields and Energy - Gravitational Fields

The distance between the centers of the Earth and the moon is 3.8 x 10^8 m. Assume that the moon moves in a circular orbit about the center of the Earth. Estimate the period of the orbit to the nearest day. *Mass of earth = 6.0 x 10^24 kg *1 day = 8.6 x 10^4 seconds *Distance between the centers of Earth and Moon = 3.8 x 10^8

A pump submerged at the bottom of a well that is 35m deep

(See attached file for full problem description with diagram) --- 6. A pump, submerged at the bottom of a well that is 35m deep, is used to pump water uphill to house that is 50m above the top of the well, as shown above. The density of water is 1,000 kg/m3. All pressures are gauge pressures. Neglect the effects of friction,

Tennis player receives shot with the ball and returns the shot

A tennis player receives a shot with the ball (0.0600 kg) traveling horizontally at 50.0 m/s and returns the shot with the ball traveling horizontally at 36.0 m/s in the opposite direction. (Assume the initial direction of the ball is in the -x direction.) (a) What is the impulse delivered to the ball by the racquet? i N ·

Ball slided down incline and encounters rough surface

1.) A 1-kg ball starting at h = 7.2 meters slides down a smooth surface where it encounters a rough surface and is brought to rest at B, a distance 26.6 meters away. To the nearest joule what is the work done by friction? 2.) To two decimal places, what is the coefficient of friction? See attached file for full problem des

Work performed by a skier: Example problem

A skier of mass 69.3 kg is pulled up a slope by a motor-driven cable. (a) How much work is required to pull him a distance of 59.0 m up a 30.4° slope (assumed frictionless) at a constant speed of 1.97 m/s? (b) A motor of what power is required to perform this task?

Physics Review

Mark the following statements true or false. If you mark it false, tell why it is false and how it could be changed to make it true. 1. If a force F acts on a particle of mass m which is moving at a speed v, we define the work done to be the change in the quantity 1/2mv^2. 2. Work is necessarily a positive quantity. 3.

Independent Wing Span Size Analysis

Question78: All birds, independent of their size, must maintain a power output of 10 to 25 watts per kilogram of body mass in order to fly by flapping their wings. (a) The Andean giant hummingbird (Pantagona Gigas) has a mass of 70g and flaps its wings ten times per second while hovering. Estimate the amount of work done

Energy is conventionally measured in Calories

Energy is conventionally measured in Calories as well as in joules. One Calorie in nutrition is one kilocalorie, defined as 1 kcal = 4186 J. Metabolizing one gram of fat can release 9.00 kcal. A student decides to try to lose weight by exercising. She plans to run up and down the stairs in a football stadium as fast as she can a