A man lifts a 10 kg sack of rice from a ground to above his head using his both hands. The sack of
rice does not experience a change in kinetic energy between the two positions. Which of the
following statement is correct?
A The work done on rice sack by gravity is less than the work done on rice sack by man.
B The work done on rice sack by gravity is more than the work done on rice sack by man
C The work done on rice sack by gravity is equal to the work done on rice sack by man.
D There is no work done on the rice sack

  1. 👍
  2. 👎
  3. 👁
  1. can u please clarifie this doubt for me

    1. 👍
    2. 👎
  2. the work done by gravity = - m g h (F down, motion direction x up)
    the work done by the man = + m g h (F up, motion direction x up)

    1. 👍
    2. 👎

Respond to this Question

First Name

Your Response

Similar Questions

  1. Physics

    A man lifts a 21.1 kg bucket from a well and does 3.1 kJ of work. How deep is the well? Assume that the man lifts the bucket at constant speed. Answer in units of m. I am not sure if I did this right: (mg)(d)= Wnet (21.1

  2. math

    A 4-pound box of rice, which is a mixture of white rice and wild rice, sells for $1.80 per pound. White rice sells for $0.75 per pound. Wild rice sells for $2.25 per pound. How many pounds of white rice are in the mixture? -White

  3. Physics

    In starting an exercise, a 1.60-m tall person lifts a 2.10 kg book from the the ground so it is 2.20m above the ground. What is the potential energy of the book relative to (a) the ground,and(b) the top of the persons head? (c)

  4. physics

    In loading a lorry a man lifts boxes each of weight 100N throughta height of 1.5 m. a)how much work does he do in lifting 1 box b)how much energy is transferred when 1 box is lifted c)if he lifts 4 boxes/minute@ what power is he

  1. physics

    Two friends are sitting in a stationary canoe. At the person at the front tosses a sack to theperson in the rear, who catches the sack 2 later. Which plot in the figure shows thevelocity of the boat as a function of time? Positive

  2. physics

    the maximum force a grocery sack can with stand and not rip is 250 N. if 20 kg of groceries are lifted from the floor to the table with an acceleration of 5 m/s squared, will the sack hold?

  3. Calculus

    A man of height 1.7 meters walks away from a 5- meter lamppost at a speed of 1.1 m/s. Find the rate at which his shadow is increasing in length. An illustration shows a man walking past a lamp post. The lamp is 5 units above the

  4. physics

    An athlete whose mass is 94.0 is performing weight-lifting exercises. Starting from the rest position, he lifts, with constant acceleration, a barbell that weighs 600 . He lifts the barbell a distance of 0.50 in a time of 2.2 .

  1. Physics

    The maximum force a grocery sack can withstand and not rip is 250 N. Calculate the greatest acceleration 20 kg of groceries can be lifted from the floor to the table such that the sack does not break.

  2. physics

    in which of the following situation is mechanical work done?a, a girl chewing a piece of chewing gum .b,an acrobat supporting two men on his shoulders. c,a man standing with heavy loads on his head. d,a man try to lifts a heavy

  3. Math

    Daniel and Imee shared a bag of rice in the ratio 4:5.Daniel receives 16 kg of the rice . What was the mass of the bag of rice that was shared? My work: 4:5-16/9=1.77777777778/1.8 =1.8*9=16.2 kg Is it correct

  4. Multiplication of Fractions

    A group of volunteers packed 198 bags of rice. Each bag contains 3 1/4 kg of rice. How many kilograms of rice did the volunteers pack?

You can view more similar questions or ask a new question.