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Work-Energy Concepts

A little red wagon with a mass of 4.60 kg moves in a straight line on a frictionless horizontal surface. It has an initial speed of 10.0m/s and then is pulled 4.0 m by a force with a magnitude of 18.0 N in the direction of the initial velocity. a) Use the work-energy relation to calculate the wagon's final speed. b) Calculate

Energy concepts

You and your bicycle have a combined mass of 95 kg. When you reach the base of an overpass, you are travelling along the road at 3.0 m/s. If the vertical height of the overpass is 5.20 m and your speed at the top is 1.5 m/s, how much work have you done in getting to the top? (Ignore friction and any inefficiency in the bike or y


See attached file. Identical charged particles: what is the potential energy in the system; if released, what is the speed of each?

Frictional Retarding Force

A worker does 300 J of work against a frictional retarding force of 15 N in pushing a power sweeper across a floor in 3.0 Seconds. If the sweeper moves with a constant speed, how fast is it going? I believe the answer is 6.7 m/s. I need to see each step and formula to solve this question.

Forces in parallel

2 forces parallel to the X axis do 14.7 Joules of work on a small tray while moving it 20.7 meters in the X direction across a gym floor. One of the forces has a value of +3.89 Newton's in the X direction. What is the other force?

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

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?

What is the 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.

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 & Energy: car, gasoline, A/C, 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?

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

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.

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

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

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.

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