1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
nirvana33 [79]
3 years ago
7

A man carries a load of 20N on his head over a horizontal distance of 20 m how much work is done by the man

Physics
1 answer:
sdas [7]3 years ago
4 0

Work done in horizontal direction = 0 as the potential energy is not changed and the change in kinetic energies : initial and final - is zero.


work done when the person carries the suitcase in vertical direction =

  = m g h = change in potential energy = 30 kg * 9.8 m/sec/sec * 10 m

  =  2940 Joules

=============

There is a force F1 lifting the body upwards. There is Weight W = m g pulling the body downwards.  The net force F2 on the body is upwards with acceleration a.


  F2 = m a  = F1 - W = F1 - m g

          a =  F1 / m - g


Work done by Force F1 with which the object is lifted = F1 . s = 230 Joules

     F1  = energy spent / distance = 230 J / 2 m  = 115 Newtons


Net Acceleration of the body = a = F1 / m - g = 115/10 - 10  = 1.5 m/sec/sec

==========================


 m = 2 kg          F = 8 Newtons        t = 12 sec

 a = F/m = 4 m/sec/sec

v = u + a t = 0 + 4 * 12 = 48 m/sec


kinetic energy = 1/2 m v² = 1/2 * 2 * 48 * 48 = 48² Joules



Read more on Brainly.in - https://brainly.in/question/71130#readmore


You might be interested in
What is the speed of a wave if the wavelength is 3 meters and the frequency is 200hz
RideAnS [48]
Wave speed = frequency * wavelength

Input the numbers into this equation :

Wave speed = 200 * 3

Work it out and you will get the answer :

Wave speed = 600 m/s
6 0
3 years ago
How much of the Moon is always illuminated one time? Explain your answer.
Natalija [7]

Answer:

50% of it .

Explanation:

50% of it is illuminated by the Sun.

6 0
3 years ago
A scientist heated a tank containing 50 g of water. The specific heat of water is 4.18 J/gºC. The temperature of the water incre
Amanda [17]
I got 5,225 by 50x4.18= 209(25)=5,225
6 0
2 years ago
What type of magnetism is present in a magnet that you use to place a photograph on the refrigerator?
Vika [28.1K]

Answer:

C) Contact

Explanation:

The magnet requires almost direct <u>contact</u> with the fridge to start its magnetic properties.

7 0
3 years ago
Read 2 more answers
I NEED AN ANSWER!
Lera25 [3.4K]

Answer:

Before sled starts to move it has a potential energy due to the elevation...and then that potential energy converted to kinetic energy due to presence of a velocity...the sled will continue to move if their is no resesive force...but however friction force is presence that cause the sled to stop....

5 0
2 years ago
Other questions:
  • 3. A crew team rows a boat at a rate of 20 km/h in still water. Beginning at time = 0 minutes, the team rows for 30 minutes up a
    14·2 answers
  • At what speed must a 950-kg subcompact car be moving to have the same kinetic energy as a 3.2×104−kg truck going 20 km/h?
    9·1 answer
  • What are 5 of the elements in the periodic table
    9·2 answers
  • If EMS waves are transverse, what conclusion can you make concerning the distances they can travel?
    5·1 answer
  • Identify which objects will accelerate to the left, which will accelerate to the right,and those that will not accelerate. Optio
    15·1 answer
  • A simple pendulum consists of a point mass suspended by a weightless, rigid wire in a uniform gravitation field. Check all that
    7·1 answer
  • A man is picked up by a tornado and dropped a quarter mile away from his home. Even though authorities estimate that his body wa
    15·1 answer
  • An evacuated tube uses an accelerating voltage of 55 kV to accelerate electrons to hit a copper plate and produce x rays. Non-re
    12·1 answer
  • What work is done by a forklift raising a 574 kg crate to a height of 1.3m in a time of 2.0 seconds?
    10·1 answer
  • Now that you know how forces affect the motions of objects, you can use the Tracker video analysis tool to create dynamic models
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!