Problem Solving. 1. A 60-kilogram woman runs up a staircase 15 m high in 20 s. a) How much power does she expend? b) What is the hp rating? 2. An electric motor with a 2 hp output drives a machine with an efficiency of 45%. What is the energy output of the machine per second?

Problem Solving. 1. A 60-kilogram woman runs up a staircase 15 m high in 20 s. a) How much power does she expend? b) What is the hp rating? 2. An electric motor with a 2 hp output drives a machine with an efficiency of 45%. What is the energy output of the machine per second?

College Physics

10th Edition

ISBN:9781285737027

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter9: Solids And Fluids

Section: Chapter Questions

Problem 2WUE: Physics Review A team of huskies performs 7 440 J of work on a loaded sled of mass 124 kg, drawing...

See similar textbooks

Related questions

Q: A 53.0 kg cheetah accelerates from rest to its top speed of 33.3 m/s. (a) How much net work (in J)…

A: a)The required work done is,

Q: A 169.5 lb hiker is able to ascend a 1,980.0 ft high slope in 1 hour and 45 minutes. (a) How much…

A: Given : F = 169.5 lb d = 1980 ft t = 1 hour 45 minutes = 6300 seconds

Q: A man pushes a lawn mower with a horizontal force of 138 N. If he pushes the lawn mower 5.2 m in 15…

Q: 2. A car of mass 1200 kg initially moving at a speed of 10m/s suddenly changes its speed to 15m/s.…

A: a) The required work done is,

Q: 13. A heavy rope, 50 ft long, weighs 0.5 lb/ft and hangs over the edge of a building 120 ft high.…

A: Length of rope = 50 ft, And weight of rope = 0.5 lb/ft Height of building = 120 ft.

Q: A sled dog can accelerate a 250 kg sled from 0 m/s to 8.5 m/s in 8 s. (8 Points) a. How far will the…

A: (a) Sleg dog has traveled Xf= 34 m in that time. (b) work done W= 9031.25 Joules

Q: 1B. A crate of mass 10.0 kg is pulled up a rough 20o- incline. The pulling force is 100 N parallel…

A: mass of crate (m) = 10 kg θ = 20oPulling force = 100 N coefficient of kinetic friction = 0.4distance…

Q: A 630-kg car speeds up from rest to 43 mph in 3.2 seconds. What is the work done on the car and what…

A: Given Data: The mass of the car is, m = 630 kg. The initial velocity is, u = 43 mph. The final…

Q: uiz Instructions Question 1 Part (a) A 50 lb weight is lifted, at a constant rate, to a height of 10…

A: Given data The weight of the object is given as Fw = 50 lb. The height to lift the object above the…

Q: An elevatoris able to raise 1,000kg to a height of 40m in 15 seconds. a. How much work does the…

Q: A vehicle pulls a cart horizontally with a force of 40 lbs at an angle of 30 above the horizontal…

A: Given data Force ( F ) = 40 lb Angle ( θ ) = 30° Speed ( v ) = 6.0 mi/h Time ( t ) = 10 minutes…

Q: A box of mass 20kg is raised to a height of 30m? a. How much work is done on the box? b. If it…

Q: A student who weighs 552 N climbs a stairway (vertical height of 3.5 m) in 20 s. (a) How much work…

Q: 1. An Eskimo returning from a successful fishing trip pulls a sled loaded with salmon. The total…

A: (a) Find the amount of work done on the sled. W=Fdcosθ=1.20×102 N5.0 mcos0°=6×102 J=600 J

Q: 3. a 0.35-kg fruit is falling from a tree with a speed of 5.0 m/s after t = 1.0 s. At t = 2.0 s, the…

Q: Shoveling snow can be extremely taxing since the arms have such a low efficiency in this activity.…

Q: An elevator is able to raise 9,800 N to a height of 47 m in 19 s. (a) How much work does the…

A: Work is the application of force f to move an object over a distance d , in the direction that the…

Q: 1. What is the work formula? a. What is the unit of measurements that each has to be in?…

A: Since you have asked multiple questions, we will solve the first question for you. If you want any…

Q: 3. A certain force applied on an object is depicted below. (a) What is the work done by the force…

Q: A student who weighs 569N climbs a stairway (vertical height of 4.3 m) in 26 s. (a) How much work is…

Q: 3. a 0.35-kg fruit is falling from a tree with a speed of 5.0 m/s after t = 1.0 s. At t = 2.0 s, the…

Q: A man of mass 80 kg runs up a flight of stairs 20 m high in 10 s. (a) how much power is used to lift…

A: Given: Mass of the man m = 80 kg Height of the stairs = 20m Time taken t = 10 seconds

Q: A 61.0 kg cheetah accelerates from rest to its top speed of 32.5 m/s. HINT (a) How much net work (in…

Q: A student who weighs 543 N climbs a stairway (vertical height of 4.2 m) in 24 s. (a) How much work…

A: Given: weight of student, W = 543 N vertical height, h = 4.2 m time taken to climb, t = 24 s

Q: (I) How much work must be done to stop a 925-kg car traveling at 95 km/h?

A: Given :- Mass of the car (m) = 925 kg Initial velocity (v) = 95 km /h (or) 26.39 m/s

Q: 3. a 0.35-kg fruit is falling from a tree with a speed of 5.0 m/s after t = 1.0 s. At t= 2.0 s, the…

Q: 10. A machine is used to move a 700 N object by 2.00 m by exerting 400 N of force through a distance…

Q: A 630-kg car speeds up from rest to 43 mph in 3.2 seconds. What is the work done on the car and what…

A: (a) Work done is equal to change in kinetic energy W1=Ekf-Eki=12mvf2-vi2=12630 kg19.2 ms2-0…

Q: A 5-kg package is pushed 2 m up a ramp that is inclined at 12o above the horizontal by a 100-N force…

A: Note : Since there are multiple sub-parts and as per guidelines we can provide solution to first…

Q: 1.An electric motor with a 2 hp output drives a machine with an efficiency of 45%. What is the…

Q: Which of the following is not an equation for getting work? Select one: a. W=Fd b. W=Fdcosθ c. W=N⋅m…

Q: 5. A 650 newton bicycle racer climbs a 500-meter hill by doing 400,000 joules of work. a) What are…

Q: A 64.0 kg cheetah accelerates from rest to its top speed of 32.5 m/s. (a) How much net work (in J)…

A: (a) According to the work energy theorem, W=∆K=12mv2-12mu2=12mv2-u2 Substitute the values, to find…

Q: 4. To pull a 50 kg crate across a horizontal frictionless floor, a worker applies a force of 210 N,…

A: Given : mass of crate, m = 50 kg θ = 20 ° Force applied by worker, f = 210 N Crate moves, d = 3.0 m

Q: 1. Sketch the following scenarios and use the appropriate formulas to solve: a) What is the kinetic…

A: a) mass (m) = 3 kg speed (v) = 4 ms

Q: s on a path that is at 25 ° to the vertical, as illustrated in ure 1). Part A Calculate the power…

Q: Q:3 a) Determine the kinetic energy of a 625-kg roller coaster car that is moving with a speed of…

Q: 1. A car with a mass of 2,000 kg drives to the top of a 100-meter hill in 15.0 seconds. Find the…

Q: 1) How much work must one do to pull the block up 13 meters? The mass is 44 kg.

Q: Baldo and Bruno reached the top of a hill 30.0 m high when they went on hiking. If Baldo is 90 kg…

Q: A horse pulls a cart horizontally with a force of 40 lb at an angle of 30- above the horizontal and…

A: Work is defined as dot product of force vector and displacement vector. Power is defined as dot…

Q: 2. A car of mass 1200 kg initially moving at a speed of 8m/s suddenly changes its speed to 15m/s in…

Q: 1. An Eskimo returning from a successful fishing trip pulls a sled loaded with salmon. The total…

A: Given data: The total mass of the sled and salmon is, m = 50.0 kg Eskimo exerts a force of magnitude…

Q: You are using a lever to lift the edge of a crate in order to slide a roller under it. The crate…

A: A) Input work done is Wi=EfEd=450 N0.8 m=360 J Output work done is Wo=RfRd=4250 N0.05 m=212.5 J

Q: 1.How much power is required to do 40 J of work in 5 seconds? 2.How much power is required for a…

A: In the questions, different data is given of work done, time, mass, and velocity to find the power…

Q: 5. A 1-kg rock is dropped from a height of 6.0 m. a. What is the mechanical energy of the rock? b.…

A: Given data: Mass of rock, m=1 kg Height, h=6 m

Concept explainers

Instantaneous Power

Power is defined in physics as the amount of energy transmitted or transformed per unit time. The watt is the unit of electricity in the International System of Units, equivalent to one joule per second.

Question

Problem Solving.

1. A 60-kilogram woman runs up a staircase 15 m high in 20 s. a) How much power does she expend? b) What is the hp rating?

2. An electric motor with a 2 hp output drives a machine with an efficiency of 45%. What is the energy output of the machine per second?

Expert Solution

This question has been solved!

Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.

SEE SOLUTION Check out a sample Q&A here

Step 1

VIEW

Step 2

VIEW

Step by step

Solved in 2 steps with 2 images

SEE SOLUTION Check out a sample Q&A here

Knowledge Booster

Learn more about

Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, physics and related others by exploring similar questions and additional content below.

Similar questions

(a) What is the average useful power output of a person who does 6.00106 J of useful work in 8.00 h? (b) Working at this rate, how long will it take this person to lift 2000 kg of bricks 1.50 m to a platform? (Work done to lift his body can be omitted because it is not considered useful output here.)
(a) What is the efficiency of an out-of-condition professor who does 2.10105J of useful work while metabolizing 500 kcal of food energy? (b) How many food calories would a well-conditioned athlete metabolize in doing the same work with an efficiency of 20%?
. An elevator is able to raise 1,000 kg to a height of 40 m in 15 s. (a) How much work does the elevator do? (b) What is the elevator’s power output?
Physics Review A team of huskies performs 7 440 J of work on a loaded sled of mass 124 kg, drawing it from rest up a 4.60-m high snow-covered rise while the sled loses 1 520 J due to friction, (a) What is the net work done on the sled by the huskies and friction? (b) What is the change in the sleds potential energy? (c) What is the speed of the sled at the top of the rise? (See Section 5.5.)
(a) How long will it take an 850-kg car with a useful power output of 40.0 hp (1hp=746W) to reach a speed of 15.0 m/s, neglecting friction? (b) How long will this acceleration take if the car also climbs a 3.00-m-high hill in the process?
Integrated Concepts (a) What force must be supplied by an elevator cable to produce an acceleration of 0.800 m/s2 against a 200-N frictional force, if the mass of the loaded elevator is 1500 kg? (b) How much work is done by the cable in lifting the elevator 20.0 m? (c) What is the final speed of the elevator if it starts from rest? (d) How much work went into thermal energy?
A student has the idea that the total work done on an object is equal to its final kinetic energy. Is this idea true always, sometimes, or never? Ii it is sometimes true, under what circumstances? If it is always or never true, explain why.
Describe a situation in which a force is exerted for a long time but does no work. Explain.
The chin-up is one exercise that can be used to strengthen the biceps muscle. This muscle can exert a force of approximately 8.00 102 N as it contracts a distance of 7.5 cm in a 75-kg male.3 (a) How much work can the biceps muscles (one in each arm) perform in a single contraction? (b) Compare this amount of work with the energy required to lift a 75-kg person 40. cm in performing a chin-up. (c) Do you think the biceps muscle is the only muscle involved in performing a chin-up?
KEY TERMS 1. work (4.1) 2. joule 3. foot-pound 4. energy (4.2) 5. kinetic energy 6. potential energy 7. gravitational potential energy 8. conservation of total energy (4.3) 9. conservation of mechanical energy 10. power (4.4) 11. watt 12. horsepower 13. kilowatt-hour 14. alternative energy sources (4.6) 15. renewable energy sources For each of the following items, fill in the number of the appropriate Key Term from the preceding list. n. _____ Time rate of doing work
In 1990, Walter Arfeuille of Belgium lifted a 281.5-kg object through a distance of 17.1 cm using only his teeth. (a) How much work was done on the object by Arfeuille in this lift, assuming the object was lifted at constant speed? (b) What total force was exerted on Arfeuilles teeth during the lift?
As a simple pendulum swings back and forth, the forces acting on the suspended object are the force of gravity, the tension in the supporting cord, and air resistance, (a) Which of these forces, if any, does no work on the pendulum? (b) Which of these forces does negative work at all times during the pendulums motion? (c) Describe the work done by the force of gravity while the pendulum is swinging.