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
dalvyx [7]
3 years ago
15

Present day Earth is in the _______.

Physics
1 answer:
Ira Lisetskai [31]3 years ago
3 0
Present day earth is in the Cenozoic era and the time period for it is 66 million years ago to today.
You might be interested in
Atomic physicists usually ignore the effect of gravity within an atom. To see why, we may calculate and compare the magnitude of
STatiana [176]

Answer:

2.27\cdot 10^{49}

Explanation:

The gravitational force between the proton and the electron is given by

F_G=G\frac{m_p m_e}{r^2}

where

G is the gravitational constant

m_p is the proton mass

m_e is the electron mass

r = 3 m is the distance between the proton and the electron

Substituting numbers into the equation,

F_G=(6.67259\cdot 10^{-11} m^3 kg s^{-2})\frac{(1.67262\cdot 10^{-27}kg) (9.10939\cdot 10^{-31}kg)}{(3 m)^2}=1.13\cdot 10^{-68}N

The electrical force between the proton and the electron is given by

F_E=k\frac{q_p q_e}{r^2}

where

k is the Coulomb constant

q_p = q_e = q is the elementary charge (charge of the proton and of the electron)

r = 3 m is the distance between the proton and the electron

Substituting numbers into the equation,

F_E=(8.98755\cdot 10^9 Nm^2 C^{-2})\frac{(1.602\cdot 10^{-19}C)^2}{(3 m)^2}=2.56\cdot 10^{-19}N

So, the ratio of the electrical force to the gravitational force is

\frac{F_E}{F_G}=\frac{2.56\cdot 10^{-19} N}{1.13\cdot 10^{-68}N}=2.27\cdot 10^{49}

So, we see that the electrical force is much larger than the gravitational force.

5 0
3 years ago
which statements about velocity are true? check all that apply. a. for velocity, you must have a number, a unit, and a direction
satela [25.4K]
a). for velocity, you must have a number, a unit, and a direction.
Yes.  This one isn't bad.  The 'number' and the 'unit' are the speed.

b). the si units for velocity are miles per hour.
No.  That's silly. 
'miles' is not an SI unit, and 'miles per hour'
is only a speed, not a velocity. 

c). the symbol for velocity is .
You can use any symbol you want for velocity, as long as
you make its meaning very clear, so that everybody knows
what symbol you're using for velocity.
But this choice-c is still wrong, because either it's incomplete,
or else it's using 'space' for velocity, which is a very poor symbol.

d). to calculate velocity, divide the displacement by time.
Yes, that's OK, but you have to remember that the displacement
has a direction, and so does the velocity.
3 0
3 years ago
If your face is 62 cm in front of a plane mirror, where is the image of your face located?
timurjin [86]

Answer:

62 cm is in front of the mirror

Explanation:

This is answers

3 0
2 years ago
Read 2 more answers
The potential of electrons in a circuit can be increased by _____.
tresset_1 [31]
<span>The potential of electrons in a circuit can be increased by the action of a battery.

</span><span>♡♡Hope I helped!!! :)♡♡
</span>
6 0
2 years ago
Read 2 more answers
The pivot point of a lever is called the fulcrum. please select the best answer from the choices provided t f user: the thread a
kkurt [141]

It is TRUE. The pivot point of a lever is called the fulcrum .

4 0
3 years ago
Read 2 more answers
Other questions:
  • According to a rule-of-thumb. every five seconds between a lightning flash and the following thunder gives the distance to the f
    10·1 answer
  • The force of gravity is an inverse square law. this means that, if you double the distance between two large masses, the gravita
    15·1 answer
  • Imagine tying a string to ball and twirling it around you.how is this similar to the moon orbiting earth?in this example what is
    6·1 answer
  • Select all of the answers that apply.
    5·2 answers
  • A rocket in deep space has an empty mass of 220 kg and exhausts the hot gases of burned fuel at 2500 m/s. What mass of fuel is n
    6·1 answer
  • Two men decide to use their cars to pull a truck stuck in mud. They attach ropes and one pulls with a force of 821 N at an angle
    12·1 answer
  • Astronomers can now report that active star formation was going on at a time when the universe was only 20% as old as it is toda
    13·1 answer
  • A notebook is on a desk the force of the notebook weight pushing down on the table is 10 in the force of the table normal force
    5·1 answer
  • Help me with this please <br>​
    8·2 answers
  • A 30kg uniform solid cylinder has a radius of 0.18m. if the cylinder accelerates at 0.023 rad/s^2 as it rotates about an axis th
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!