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
Bumek [7]
4 years ago
12

What structure allows only certain things to pass in and out of the cells

Physics
1 answer:
alexira [117]4 years ago
5 0
The cell membrane allows only certain things to pass in and out of the cells.
You might be interested in
Nuclear chain reactions within power plants do NOT produce bomb-like explosions primarily because the ________.
Gelneren [198K]

Answer: D. Density of uranium within nuclear fuel rods is insufficient to become explosive

Explanation: Nuclear power plants use the same fuel as nuclear bombs, i.e. radioactive Uranium-235 isotope. However, in a nuclear power plant, the energy is released more slowly unlike in a nuclear bomb. <em>The energy released is through nuclear fission, and radioactive decay occurs at the same rate as in nuclear bombs. therefore, option A, B</em><em> </em><em>and C are incorrect.</em>

The primary reason why nuclear chain reactions within power plants do NOT produce bomb-like explosions is because the uranium fuel rods used in electricity generation is not sufficiently enriched in Uranium-235 to produce a nuclear detonation. This is the same idea in option D which is the correct option.

6 0
3 years ago
The change in pitch of a train's horn as it passes while you are standing still can be explained by
RSB [31]
The change in pitch of a train's horn as it passes while you are standing still can be explained by the Doppler effect. The correct option among all the options given in the question is option "A". When the sound source from the horn of the train comes closer, the sound seems to come closer each time a sound wave gets emitted. So it comes closer to us in a bunched form. The reverse happens when the train has just passed with each emitted sound going further and further away. The frequency of the sound seems to get lower as the train moves further away. 
4 0
3 years ago
Read 2 more answers
If you push a crate across a factory floor at constant speed in a constant direction, what is the magnitude of the force of fric
poizon [28]

Answer:

The magnitude of the force of friction equals the magnitude of my push

Explanation:

Since the crate moves at a constant speed, there is no net acceleration and thus, my push is balanced by the frictional force on the crate. So, the magnitude of the force of friction equals the magnitude of my push.

Let F = push and f = frictional force and f' = net force

F - f = f' since the crate moves at constant speed, acceleration is zero and thus f' = ma = m (0) = 0

So, F - f = 0

Thus, F = f

So, the magnitude of the force of friction equals the magnitude of my push.

3 0
3 years ago
A hummingbird can flutter its wings 4,800 times per minute. What is the frequency of wing flutters per second?What is the period
wariber [46]

A hummingbird can flutter it's wings about 80 times per second.

4,800 divided by 60=80

5 0
4 years ago
Read 2 more answers
A piece of taffy slams into and sticks to another identical piece of taffy that is at rest. The momentum of the two pieces stuck
-Dominant- [34]

Answer:

C. 50%

Explanation:

Lets consider that the mass of taffy is m and its initial velocity is u and final velocity is v. Momentum is conserved so we can write it as,

mu = 2mv\\v = \frac{u}{2} \\

The initial kinetic energy = \frac{mu^{2} }{2}

As the Kinetic energy partly converted into heat.

The final kinetic energy = \frac{m(\frac{u}{2})^{2}  }{2} = \frac{mu^{2} }{4}

Change in the kinetic energy = \frac{mu^{2} }{2} - \frac{mu^{2} }{4} = \frac{mu^{2} }{4}

now we can determine the fraction of kinetic energy that has turned into heat

                           = \frac{Heat energy}{initial K.E} = \frac{\frac{mu^{2} }{4} }{\frac{mu^{2} }{2} }  = 1/2

                           = 50%

3 0
4 years ago
Other questions:
  • The movement of atoms is an example of what type of energy?
    11·1 answer
  • Equal and opposite forces that act on the same object are called __________ forces. A. balanced B. operative C. neutral D. unbal
    12·1 answer
  • The metric unit of force is the Newton (N), which is kg∙m/s^2. Convert 10 mg∙cm/s^2 to Newtons. Be careful when working with uni
    11·2 answers
  • A cube made Of an unknown material has a height of 9 symeters the mass of this cube is 3645 g. calculate the density of this cub
    8·1 answer
  • Rotational inertia about the midpoint of an object becomes greater with _______.
    6·1 answer
  • During a total solar eclipse, the Earth, Sun, and Moon are arranged in a line, and light from the Sun is blocked out of view for
    8·1 answer
  • Please help!!!!!!!!
    15·1 answer
  • A student drops an egg from the roof of their house onto a trampoline. The egg feels a change in momentum of 2.2 kg^ * m/s in 1.
    12·1 answer
  • A baseball with mass of 0.145 kg is thrown straight down at the ground. At a particular speed, it has a drag force of 0.4 N acti
    9·1 answer
  • A sports car can move 100.0 m in the first 3.8 s of constant acceleration. What is the car's acceleration?
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!