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
skelet666 [1.2K]
4 years ago
7

Okay guys I need serious help here plz!!!

Physics
1 answer:
stich3 [128]4 years ago
3 0
Lithium-Dull

Sodium-Dull

Potassium- Dull

Rubidium- Dull

Cesium- Both

Francium- Shiny

You might be interested in
Lions can run at speeds up to approximately 80.0 km / h. A hungry 109 kg lion running northward at top speed attacks and holds o
sukhopar [10]

Answer:

17.34 m/s

Explanation:

Given:

Mass of lion (m₁) = 109 kg

Initial speed of lion (v₁) = 80.0 km/h (Northward direction)

Mass of gazelle (m₂) = 39.0 kg

Initial speed of gazelle (v₂) = 78.5 km/h (Eastward direction)

Final velocity of both lion and gazelle is, v_f=?

First, let us convert the speeds from km/h to m/s using the conversion factor.

We know that, 1 km/h = 5/18 m/s

Therefore,

v_1= 80.0\ km/h=80\times \frac{5}{18}=22.22\ m/s\\\\v_2=78.5\ km/h=78.5\times \frac{5}{18}=21.81\ m/s

Now, the concept of conservation of total momentum is used here as this is a case of perfectly inelastic collision. In inelastic collision, the masses move together with same velocity after collision.

Here, as the lion and gazelle are moving in directions at right angles to each other, the vector sum of their momentums will give the net initial momentum of the system.

So, initial momentum is given as:

P_i=\sqrt{P_1^2+P_2^2}\\\\Where,\\\\P_1\to initial\ momentum\ of\ lion\\P_2\to initial\ momentum\ of\ gazelle

Now, we calculate P₁ and P₂.

P_1=m_1v_1=(109\ kg)(22.22\ m/s) = 2421.98\ Ns\\\\P_2=m_2v_2=(39\ kg)(21.81\ m/s) = 850.59\ Ns

Therefore, the net initial momentum of the system is given as:

P_i=\sqrt{(2421.98)^2+(850.59)^2}=2567\ Ns

The final momentum of the system is given as:

P_f=(m_1+m_2)(v_f)\\\\P_f=(109+39)v_f\\\\P_f=148v_f

From the law of conservation of momentum, the final momentum is equal to the initial momentum. So,

P_f=P_i\\\\148v_f=2567\\\\v_f=\frac{2567}{148}=17.34\ m/s

Therefore, the final speed of the lion-gazelle system is 17.34 m/s

3 0
3 years ago
3. How can the U.S. economy grow if we import more goods and services?
Naddik [55]

Answer:

A trade deficit therefore occurs when a country spends more on imports than it receives in exports. A budget deficit, in the context of the government, instead occurs when there is more federal spending than revenue taken in from taxes, duties, fines, and other fees.

Explanation:

~Luna Loves

4 0
2 years ago
Read 2 more answers
Which person will most likely hear the loudest sound?
Nataliya [291]

Person standing on A will hear the loudest sound

Explanation:

The intensity of a sound wave (which is proportional to the loudness of the sound) follows an inverse square law, which is:

I\propto \frac{1}{r^2}

where

I is the intensity of the wave

r is the distance from the source of the sound

This equation means that the intensity of the sound wave (and therefore, its loudness) is inversely proportional to the square of the distance  from the source: therefore,

  • As we get closer to the source of sound, the loudness increases
  • As we move away from the source of sound, the loudness decreases

Therefore, the person that will hear the loudest sound is the one standing closer to the source, and therefore person A.

Learn more about sound waves:

brainly.com/question/4899681

#LearnwithBrainly

6 0
4 years ago
Read 2 more answers
I need help on this question, please.
frez [133]

Answer:

|X| = 72 cm

Explanation:

We need to find the magnitude of vector X.

Vector Y = 21 cm

Vector Z = 75 cm

We know that, the magnitude of resultant vector is given by :

Z={X^2+Y^2} \\\\X^2=Z^2-Y^2\\\\X^2=(75)^2-(21)^2\\\\X=72\ cm

So, the value of magnitude of vector X is 72 cm

4 0
3 years ago
The greenhouse effect is
klio [65]
It a because I learn it in class today
6 0
3 years ago
Read 2 more answers
Other questions:
  • An old truck compresses a spring scale at the junkyard by 25 cm. The spring constant for the industrial scale at the junkyard is
    12·2 answers
  • Which of the following statements is true? Group of answer choices The shortest wavelength of light is the visible light, which
    13·1 answer
  • Which two statements about an electric motor are true?
    8·2 answers
  • What has research determined about the orbit of an electron around a nucleus?
    13·1 answer
  • A potter’s wheel moves from rest to an angular speed of 0.50 rev/s in 28.9 s. Assuming constant angular acceleration, what is it
    11·1 answer
  • You walk six blocks east along 12th Street, then three blocks west, then one block east, then six blocks east, then seven blocks
    14·1 answer
  • The Atomic number tells us the number of ____ in an atom.
    8·2 answers
  • A five pulley system is used to lift a load
    14·1 answer
  • PLEASE HELP!!
    6·2 answers
  • Would u rather/ get ur dream car or live in a van and never pay taxes
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!