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
ser-zykov [4K]
3 years ago
12

Which force requires contact?

Physics
2 answers:
Minchanka [31]3 years ago
8 0

Answer:

A

Explanation: A is a example of Air resistance force, which is a contact force.

rosijanka [135]3 years ago
6 0
Answer is A. The force exerted by air as an object moves through it.
You might be interested in
What is the concentration of H^ + at apH = 2 ? Mol / L What is the concentration of H^ + ions at apH = 6 ? Mol/L How many more H
Nonamiya [84]

Answer:

The concentration of hydrogen ion at pH is equal to 2 := [H^+]=0.01 mol/L

The concentration of hydrogen ion at pH is equal to 6 : [H^+]'=0.000001 mol/L

There are 0.009999 more moles of  H^+ ions in a solution at a pH = 2 than in a solution at a pH = 6.

Explanation:

The pH of the solution is the negative logarithm of hydrogen ion concentration in an aqueous solution.

pH=-\log [H^+]

The hydrogen ion concentration at pH is equal to 2 = [H^+]

2=-\log [H^+]\\

[H^+]=10^{-2}M= 0.01 M=0.01 mol/L

The hydrogen ion concentration at pH is equal to 6 = [H^+]

6=-\log [H^+]\\\\

[H^+]=10^{-6}M= 0.000001 M= 0.000001 mol/L

Concentration of hydrogen ion at pH is equal to 2 =[H^+]=0.01 mol/L

Concentration of hydrogen ion at pH is equal to 6 = [H^+]'=0.000001 mol/L

The difference between hydrogen ion concentration at pH 2 and pH 6 :

= [H^+]-[H^+]' = 0.01 mol/L- 0.000001 mol/L = 0.009999 mol/L

Moles of hydrogen ion in 0.009999 mol/L solution :

=0.009999 mol/L\times 1 L=0.009999 mol

There are 0.009999 more moles of  H^+ ions in a solution at a pH = 2 than in a solution at a pH = 6.

8 0
3 years ago
What is the wavelength of an earthquake wave if it has a speed of 7 km/s and a frequency of 3 Hz?
Phantasy [73]
V=fλ
7=3xλ
λ=7÷3
λ=2.333km
5 0
3 years ago
Students measured the mass of 25.0 mL of water and found it be 25.4 g. The accepted mass is 25.0 g. What is the percent error of
Andre45 [30]
Well first of all, I think the students may have been correct. 
If they didn't use distilled water, and if it wasn't exactly at 
standard temperature, then the mass of  25.0 mL  could
very well be  25.4 grams.  We don't know that there was
any 'error' in their measurement at all.
But the question says there was, so we'll do the math:

The 'error' was  (25.4 - 25.0) = +0.4 gram

As a fraction of the 'real' value, the error was

                            +0.4 / 25.0  =  +0.016 .

To change a decimal to a percent, move the
decimal point two places that way  ===> .

                           + 0.016  =  +1.6 % .

     
Their measurement was 1.6% too high.

Let's not call it an 'error'.  Let's just call it a 'discrepancy'
between the measured value and the 'accepted' value.  OK ?
4 0
3 years ago
Read 2 more answers
When work is done and a force is transferred which choice describes the movements of the object?
Arisa [49]
When work is done and a force is transferred an object must move
3 0
4 years ago
Which of newton's laws explains why your hands get red when you press them hard against a wall
kirill115 [55]
The Newton’s law that explains why the hands get red when you press them hard against a wall is Newton’s third law. When one body exerts a force on a second body, the second body simultaneously exerts a force equal in magnitude and opposite direction on the first body.
5 0
3 years ago
Other questions:
  • Seafloor spreading causes an oceanic plate to collide with a continental plate. If it were to go through the whole tectonic cycl
    15·2 answers
  • A body is suspended from the ceiling with two wires that make an angle of 40° with the ceiling. The weight of the body is 150N.
    13·1 answer
  • A boy slides a book across the floor, using a force of 5 N over a distance of 2
    7·1 answer
  • A planet similar to the Earth has a radius 7.4 × 106 m and has an acceleration of gravity of 10 m/s 2 on the planet’s surface. T
    7·1 answer
  • Two identical balls are at rest and side by side at the top of a hill. You let one ball, A, start rolling down the hill. A littl
    14·1 answer
  • A has the magnitude 14.4 m and is angled 51.6° counterclockwise from the positive direction of the x axis of an xy coordinate sy
    6·1 answer
  • What is the energy of light that must be absorbed by a hydrogen atom to transition an electron from n = 3 to n = 5?
    11·1 answer
  • a red kangaroo can hop at speeds of 65 km/hr. how much time will it take the kangaroo to hop 0.25 km at that speed?
    10·1 answer
  • When the sphere makes a complete revolution around its circular path, does it spend:_______
    12·1 answer
  • Help me for physics please
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!