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
Evgen [1.6K]
4 years ago
5

A ball is thrown straight upward. How does the sign of the work done by gravity while the ball is traveling upward compare with

the sign of the work done by gravity while the ball is traveling downward?A. Work done by gravity is negative while the ball is traveling upward and positive while the ball is traveling downward.B. Work done by gravity is positive while the ball is traveling both upward and downward.C. Work done by gravity is positive while the ball is traveling upward and negative while the ball is traveling downward.D. Work done by gravity is negative while the ball is traveling both upward and downward.
Physics
1 answer:
ankoles [38]4 years ago
3 0

Answer:

A.

Explanation:

  • According to the work energy theorem, the work done by external forces on a mass, must equal to the change in kinetic energy.
  • When thrown upward, the change in kinetic energy is negative, due to it must have some initial velocity, which it will diminishing while going upward, as gravity is slowing down it.
  • So, in this part of the trajectory, work done by gravity (only force acting on the ball if we neglect air resistance) must be negative.
  • In the downward part of the trajectory, as the change in kinetic energy is positive (the ball is speeding up when falling), the work done by gravity must be positive too.
  • So, the option A is the one that is true.
You might be interested in
HELP PLS! :/
zlopas [31]

Explanation:

formula: Vi = Vf - (at)

Vi: intial velocity

Vf: final velocity

a: acceleration

t: time

fill in formula with the numbers you are given

Vi= 41.6m - ((9.81 m/s^2)(1.89s))

parenthesis first according to pemdas

Vi= 41.6m - 18.54m/s

Answer: 23.06m/s

disclaimer: I havent done physics in awhile so I have no idea if this is right. just an attempt to help steer you in the right direction hopefully. good luck

7 0
3 years ago
During exercise, the supply of oxygen and __________ to muscles increases. What one word completes the sentence?
kondaur [170]

Answer:

Glucose

Explanation:

During exercise, muscles need more energy. They get this energy by aerobic respiration, which uses oxygen and glucose to release energy.

Note: If the body fails to supply oxygen to the muscles fast enough, the muscles will produce energy by anaerobic respiration, which is not as effective as aerobic respiration in addition to producing lactic acid.

7 0
3 years ago
Read 2 more answers
A projectile is fired into the air at a 35o angle to the horizontal and an initial velocity of 120 m/s. what are the x and y com
Anarel [89]

Answer:

See below

Explanation:

X component = 120 * cos 35° =  98.298 m/s

Y component = 120 * sin 35° = 68.829 m/s

4 0
2 years ago
Sphere A has an excess of 10 ^ 15 electrons and sphere B has an excess of 10 ^ 13 protons. They are separated by 2.0 m. What is
klasskru [66]
The answer is B
I used these equations then i putted it together.
Charge = number of ( electron or proton ) x charge of ( electron or proton )
Force = k x (q1 q2)/r²

4 0
3 years ago
Whta is the mechanical advantage when the effort force is 20 and the resistance force is 5
pogonyaev
The mechanical advantage would be 4. 20/5=4
7 0
3 years ago
Other questions:
  • A trait that can only be inherited by a female would be a
    11·1 answer
  • Which value is equivalent to 178 centimeters?
    11·1 answer
  • The fundamental frequency of a pipe that is open at both ends is 564 hz . part a how long is this pipe?
    7·2 answers
  • What is the kinetic energy of a 150 kg bear running at 3 m/s?
    7·1 answer
  • What is the mass of an atom with six protons, seven neutrons, and eight electrons?
    7·1 answer
  • PLEASE help!!
    12·1 answer
  • A horizontal force of 150 N is used to push a 38.0 kg packing crate a distance of 6.85 m on a rough horizontal surface. If the c
    5·1 answer
  • 2.1
    10·1 answer
  • The two blocks are connected by a light string that passes over a frictionless pulley with a negligible mass. The 2 kg block lie
    5·1 answer
  • If a 5kg ball is traveling at 20 m/s and it’s stopped in 4s, what’s the impulse on the ball?
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!