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
Mrrafil [7]
4 years ago
9

Calculate the acceleration if you push with a 20 n horizontal force on a 4 kg block on a horizontal friction-free air table.

Physics
1 answer:
My name is Ann [436]4 years ago
8 0
Force = mass * acceleration

20 = 4a
20/4 = a
5 m/s^2 = a
You might be interested in
#1 Not sure where to start. This is for AP Physics!
yaroslaw [1]

First,

\rho=\dfrac mV

where \rho is density, m is mass, and V is volume. We can compute the volume of the roll:

2.7\,\dfrac{\mathrm g}{\mathrm{cm}^3}=\dfrac{1275\,\mathrm g}V

\implies V\approx472.22\,\mathrm{cm}^3\approx4.72\,\mathrm m^3

When the roll is unfurled, the aluminum will be a rectangular box (a very thin one), so its volume will be the product of the given area and its thickness x. Note that we're assuming the given area is not the actual total surface area of the aluminum box, but just the area of the largest face (i.e. the area of one side of the unrolled sheet of aluminum).

So we have

V=Ax

where A is the given area, so

4.72\,\mathrm m^3=\left(18.5\,\mathrm m^2\right)x

\implies x\approx0.255\,\mathrm m=255\,\mathrm{mm}

If we're taking significant digits into account, the volume we found would have been V=470\,\mathrm m^3, in turn making the thickness x=250\,\mathrm{mm}.

8 0
3 years ago
Jill can use a force of 12.0 N to lift a single box up 5.00 m. How many of these boxes must she lift it in a minute to use 60.0
Mama L [17]

Answer:

60 boxes

Explanation:

The work done by lifting a single box is equal to the force applied (the weight of the box) times the displacement of the box:

W_1 = Fd=(12.0 N)(5.00 m)=60 J

Power is related to the work done by the equation:

P=\frac{W}{t}

where W is the work done and t is the time. In this problem, we are told that the power used is P=60.0 W, while the time taken is t = 1 min = 60 s, so the total work done must be

W=Pt=(60.0 W)(60 s)=3600 J

Therefore, the number of boxes that she has to lift in order to use this power is the total work divided by the work done in lifting each box:

N=\frac{W}{W_1}=\frac{3,600 J}{60 J}=60

5 0
4 years ago
How has globalization led to underdeveloped countries?
Readme [11.4K]

Answer: Economic growth is the main channel. Globalization can affect poverty. when countries open up to trade, they tend to grow faster and living standards do tend to increase.

Explanation: I hope this helps :)

5 0
2 years ago
Light of frequency 2.5 x 1015 Hz illuminates a
Nikitich [7]

Answer:

h f = W + KE

Input energy equals work function plus KE of emitted electron

W = 6.63E-34 * 2.5E15 - 6.3 * 1.6E-19

W = 6.63 * 2.5 * 10^-19 - 10.1 * E-19 ev     (1ev = 1.6E-19 J)

W = (16.6 - 10.1)E-19 = 6.5E-19 J

h f = 6.5E-19 J        for electrons to be emitted with zero KE

f = 6.5E-19 / 6.63E-34 = .98E-15 / sec = 9.8E-14 / sec  (threshold)

3 0
3 years ago
Which of the following is an example of velocity?
saveliy_v [14]

Answer:

C

Explanation:

b is 55 miles per hour south  or 55mph[South]

the important part to understand is that velocity is a vector meaning it also has to have a direction, in this case south. That is why a (2m/s) is not a velocity, however 2m/s is a speed.

8 0
3 years ago
Other questions:
  • A nurse counts 66 heartbeats in one minute. What is the period of the hearts oscillation? In minutes
    12·1 answer
  • A horizontal force of 90.0 N is required to push a 75kg object along a horizontal surface at a constant speed. What is the magni
    13·1 answer
  • Corrosion is the tendency of a metal to revert back to its natural state.
    8·1 answer
  • A particle of mass 4.00 kg is attached to a spring with a force constant of 100 N/m. It is oscillating on a frictionless, horizo
    12·1 answer
  • I forgot how to breath
    15·2 answers
  • Bird bones have air pockets in them to reduce their weight—this also gives them an average density significantly less thanthat o
    15·1 answer
  • The social interaction theory explains that the purpose of aggression is to control another person’s behavior.
    5·2 answers
  • If i ask wat r the application of simple machine some of u will say-----> Simple machines that are widely used include the wh
    10·1 answer
  • What is an earthquake​
    8·2 answers
  • E) the time it takes the car to reach 20.0ms-1​
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!