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
Alexandra [31]
4 years ago
9

Choose all of the statements that are true about electromagnets: 1. Electromagnets are permanent and always have a magnetic fiel

d around them. 2. electromagnets can be made stronger by adding more coils to the solenoid. 3. electromagnets can be made stronger by increasing the strength of the electrical source. 4. none of the above.
Physics
1 answer:
Nitella [24]4 years ago
7 0

Answer:

2. electromagnets can be made stronger by adding more coils to the solenoid.

3. electromagnets can be made stronger by increasing the strength of the electrical source.

Explanation:

Electromagnets are not permanent, they act as magnets when current runs through its coils. They can be stronger by increase the current that goes through the coil surrounding them,. This can be done two ways: 1) increasing the actual current intensity, or 2) increasing the number of coils that wrap around them.

You might be interested in
If an inelastic collision takes place, during the collision, what is conserved?
sergij07 [2.7K]

Answer:

An inelastic collision is a collision in which there is a loss of kinetic energy. While momentum of the system is conserved in an inelastic collision, kinetic energy is not.

8 0
3 years ago
At what speed does a clock move if it is measured to run at a rate two-fifths the rate of a clock at rest with respect to an obs
Liono4ka [1.6K]

Answer:

0.44c

Explanation:

We know that

Time interval at speed (ts)= time interval at rest(tr) / gamma

where

gamma = √[1-(v/c)²]

ts = tr / gamma

tr/ts = gamma

But

Ss/Sr = gamma

Where

Sr = clock speed at rest, Ss at speed):

So

√[1-(v/c)²] = 2/5

1 - (v/c)² = 4/25

(v/c)²= 5/25

v/c = √5 / 5

v = 0.444c

4 0
3 years ago
A baby stroller is a rest on top of a hill which is 10 m high. The stroller and baby have a mass of 20 kg. What is the potential
NISA [10]
Potential energy = mass x gravity x height
= 20 x 9.81 x 10
= 1962J
3 0
3 years ago
Read 2 more answers
Chris shoots an arrow up into the air. The height of the arrow is given by the function h(t) = - 16t2 + 32t + 26 where t is the
seropon [69]

Answer:

The maximum height of the arrow is 42 (and the units given for the height)

Explanation:

Everything is easier if you make a graph, you can give values to t and replace that values in the function, for example:

When t=0

h(0)=-16(0^{2})+32(0)+26

h(0)=26

If you give some values to t you can see how the trajectory of the arrow is (please look the graphic below)

Now, to find the maximum you have to find the derivative of the function that describes the height of the arrow:

h(t)=-16t^{2}+32t+26

h'(t)=-32t+32

Then you have to take the derivative, and equals to zero to find t:

-32t+32=0

-32t=32

t=1

That is in the time of 1 second the arrow has its maximum height.

Now you have to replace this value in the original function, to find the height of the arrow:

h(1)=-16(1^{2})+32(1)+26

h(1)=-16+32+36

h(1)=42

4 0
3 years ago
What do the iron filings around this magnet show?
Anarel [89]

Answer:

the opposite connections of the poles

Explanation:

6 0
3 years ago
Other questions:
  • Which of the following is not a vector?<br><br> Velocity <br> Momentum<br> Acceleration <br> Mass
    9·2 answers
  • PLease Help !!! A.S.A.P!!! will be marked as brainlest !!!!! 16 points
    13·2 answers
  • 5. A little boy tries to push a heavy cupboard. He uses a force of 400 N, but he is unable to move
    12·1 answer
  • HELP PLEASE <br>what is the total resistance an current in the diagram below
    15·1 answer
  • A proton is first accelerated from rest through a potential difference V and then enters a uniform 0.750-T magnetic field orient
    10·1 answer
  • If you push a box across the floor, the box experiences what kind of friction?
    13·2 answers
  • What type of conversion is taking place when natural gas is used to heat water?
    10·1 answer
  • Help plz, will give brainliest!!!!
    9·2 answers
  • 26 POINTS!! will give brailest! can anyone help me? if you can't well, Merry Christmas!
    8·1 answer
  • The density of iron is 7.8 g/cm3, what is the mass of 5cm3 of it?
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!