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
emmainna [20.7K]
3 years ago
12

An object with a mass of 20 kg has a net force of 80 N acting on it. What is the acceleration of the object

Physics
1 answer:
Marat540 [252]3 years ago
3 0

Answer:

a = 4m/s²

Explanation:

a= f/m

a = 80/20

a = 4m/s²

You might be interested in
Now our wavelength is getting longer
aleksley [76]
This makes frequency lower as well as the pitch we hear.
6 0
3 years ago
Read 2 more answers
Help me plaese on this
Crazy boy [7]

Answer:

visible light waves

Explanation:

what

5 0
2 years ago
Read 2 more answers
Opposite chargers and like charges
cluponka [151]
Opposite charges attract
Like charges repel
7 0
3 years ago
Read 2 more answers
A 75 N box of oranges is being pushed across a horizontal floor. As it moves, it is slowing at a constant rate of 0.90 m/s each
shusha [124]

Answer:

μk = 0.26885

Explanation:

Conceptual analysis

We apply Newton's second law:

∑Fx = m*a (Formula 1)

∑F : algebraic sum of the forces in Newton (N)

m : mass in kilograms (kg)

a : acceleration in meters over second square (m/s²)

Data:

a= -0.9  m/s²,  

g = 9.81 m/s² : acceleration due to gravity

W= 75 N :  Block weight

W= m*g  

m =  W/g = 75/9.8= 7.65 kg :  Block mass

Friction force : Ff

Ff= μk*N

μk: coefficient of kinetic friction

N : Normal force (N)  

Problem development

We apply the formula (1)

∑Fy = m*ay    , ay=0

N-W-25 = 0

N = 75 +25

N= 100N

∑Fx = m*ax    

20-Ff= m*ax    

20-μk*100 = 7.65*(-0.90 )

20+7.65*(0.90) = μk*100

μk = ( 20+7.65*(0.90)) / (100)

μk = 0.26885

4 0
3 years ago
Potassium is a crucial element for the healthy operation of the human body. Potassium occurs naturally in our environment and th
gregori [183]

Complete Question

Potassium is a crucial element for the healthy operation of the human body. Potassium occurs naturally in our environment and thus our bodies) as three isotopes: Potassium-39, Potassium-40, and Potassium-41. Their current abundances are 93.26%, 0.012% and 6.728%. A typical human body contains about 3.0 grams of Potassium per kilogram of body mass. 1. How much Potassium-40 is present in a person with a mass of 80 kg? 2. If, on average, the decay of Potassium-40 results in 1.10 MeV of energy absorbed, determine the effective dose (in Sieverts) per year due to Potassium-40 in an 80- kg body. Assume an RBE of 1.2. The half-life of Potassium-40 is 1.28 * 10^9years.

Answer:

The potassium-40 present in 80 kg is  Z = 0.0288 *10^{-3}\ kg

The effective dose absorbed per year is  x = 2.06 *10^{-24} per year

Explanation:

From the question we are told that

      The mass of potassium in 1 kg of human body is m =  3g= \frac{3}{1000} =  3*10^{-3} \ kg

      The mass of the person is M = 80 \ kg

       The abundance of Potassium-39 is   93.26%

        The abundance of Potassium-40 is   0.012%

         The abundance of Potassium-41 is   6.78 %

         The energy absorbed is  E =  1.10MeV = 1.10 *10^{6} * 1.602 *10^{-19} = 1.7622*10^{-13} J

Now  1 kg of human body contains       3.0*10^{-3}\ kg of  Potassium

So      80 kg of human body contains      k kg of  Potassium

=>   k = \frac{ 80 * 3*10^{-3}}{1}

     k = 0.240\  kg

Now from the question potassium-40 is  0.012% of the total  potassium so

     Amount of potassium-40  present is mathematically represented as

            Z = \frac{0.012}{100}  * 0.240

            Z = 0.0288 *10^{-3}\ kg

The effective dose (in Sieverts) per year due to Potassium-40 in an 80- kg body is mathematically evaluated as

           D =  \frac{E}{M}

Substituting values

          D =  \frac{1.7622*10^{-13}}{80}

            D =  2.2*10^{-15} J/kg

Converting to Sieverts

We have

           D_s = REB * D

           D_s = 1.2 * 2.2 *10^{-15}

           D_s =  2.64 *10^{-15}

So

     for half-life (1.28 *10^9 \ years)  the dose is  2.64 *10^{-15}

     Then for 1  year the dose would be  x

=>         x = \frac{2.64 *10^{-15}}{1.28 * 10^9}

             x = 2.06 *10^{-24} per year      

7 0
3 years ago
Other questions:
  • Slow moving vehicles that travel at a speed less than ___ mph will have an orange reflective triangle with red around the edges
    7·1 answer
  • Which device provides electrical energy to run an electric circuit?
    13·1 answer
  • Which category of galaxy does not have a distinctive shape?
    15·2 answers
  • You can increase friction by
    14·1 answer
  • A major strike-slip earthquake on the San Andreas fault in California will cause a catastrophic tsunami affecting residents of S
    10·1 answer
  • A moving car has kinetic energy. If it speeds up until it is going four times faster than before, how much kinetic energy does i
    13·1 answer
  • A ball is thrown upward. At a height of 10 meters above the ground, the ball has a potential energy of 50 Joules (with the poten
    12·1 answer
  • Which type of wave has a wave perpendicular to the disturbance
    9·1 answer
  • Is it accurate to describe the physical universe as composed of only matter and energy?
    15·2 answers
  • Please help thank you!
    6·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!