Question
Asked Dec 8, 2019
1 views
A 68.1 kg runner has a speed of 3.50 m/s at one instant during a long-distance event.
 
 For (a) Apply the definition of kinetic energy. For (b) use the work-energy theorem.
 
(a)
What is the runner's kinetic energy at this instant (in J)?
 
(b)
How much net work (in J) is required to triple her speed?
 
 
check_circle

Expert Answer

Step 1

(a) The runner’s kinetic energy at the instant is

help_outline

Image Transcriptionclose

KE, = -m Новлья16.50а/5 2 (68.1kg)(3.50m/s)* = 417.1J

fullscreen
Step 2

(b) The kinetic energy required...

help_outline

Image Transcriptionclose

(1/2)nn KE, (1/2)m(3v) KE, KE, = 9KE, = 9(417.1J) = 3753.9J

fullscreen

Want to see the full answer?

See Solution

Check out a sample Q&A here.

Want to see this answer and more?

Solutions are written by subject experts who are available 24/7. Questions are typically answered within 1 hour.*

See Solution
*Response times may vary by subject and question.
Tagged in

Science

Physics

Work,Power and Energy

Related Physics Q&A

Find answers to questions asked by student like you
Show more Q&A
add
question_answer

Q: An air-track glider is attached to a spring on a frictionless horizontal surface. The air-track glid...

A: Write the expression for the maximum speed of the air-track glider in the oscillation, and solve for...

question_answer

Q: If I  drove 55 kilometers per hour, how long would the trip take one way? It takes 452 miles for the...

A: The speed of the vehicle,

question_answer

Q: A 7.80-g bullet moving at 650 m/s penetrates a tree trunk to a depth of 5.70 cm. (a) Use work and en...

A: Given:Mass of the bullet = 7.50 g = 0.00750 kgSpeed of the bullet = 650 m/sDepth of embedding in the...

question_answer

Q: A horizontal pipe 17.0 cm in diameter has a smooth reduction to a pipe 8.50 cm in diameter. If the p...

A: Given,

question_answer

Q: At what distance (in mm) from a long, straight wire carrying a current of 28 A will the magnitude of...

A: Given,

question_answer

Q: 29. Jonathan is riding a bicycle and encounters a hill of height AMT 7.30 m. At the base of the hill...

A: a)The required external work done is,

question_answer

Q: Using energy considerations, calculate the distance the 65.0-kg baseball player slides,given that hi...

A: The initial kinetic energy of the system is

question_answer

Q: what would happen to a life-form if the information handed down to offspring was always the same? ho...

A: There would be no genetic mutations and thus no adaptations to the environment.  This would be great...

question_answer

Q: A ball is thrown horizontally from the top of a 60.0 m building and lands 100.0 m from the base of t...

A: Here,