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
Kazeer [188]
3 years ago
6

An athlete is running a 5-km race at an average speed of 8 km/h. She has to stop to tie her shoe. After tying her shoe, she cont

inues running at 8 km/h. Why would her average speed for the entire race be less than 8 km/h?.
Chemistry
1 answer:
gladu [14]3 years ago
3 0
Because she has to stop to tie her shoe which will slow down her average speed for the entire race.
You might be interested in
Write a hypothesis about the effect of dry conditions on earthworm behavior. Use the "if . . . then . . .
Vlada [557]

sorry about the late response...

<u>If an earthworm is exposed to dry conditions, then it will retreat to a moist place because its skin needs to stay moist for the earthworm to survive.</u>

4 0
3 years ago
Read 2 more answers
What mass of sodium bicarbonate do you start with
valentina_108 [34]

Answer:

84.007 g/mol

Explanation:

welcome

5 0
3 years ago
What is the density of an 84.7 g sample of an unknown substance if the sample occupies 49.6cm cubed
Ahat [919]

Answer:

             1.70 g.cm⁻³

Solution:

Data Given;

                   Mass  =  84.7 g

                   Volume  =  49.6 cm³

                   Density  =  ?

Formula Used;

                   Density  =  Mass ÷ Volume

Putting values,

                   Density  =  84.7 g ÷ 49.6 cm³ 

                   Density  =  1.70 g.cm⁻³

7 0
3 years ago
Design a test to determine whether thorium-234 also emits particles. First, explain how Rutherford’s experiment measured positiv
liubo4ka [24]

The characteristics of the α and β particles allow to find  the design of an experiment to measure the ²³⁴Th particles is:

  • On a screen, measure the emission as a function of distance and when the value reaches a constant, there is the beta particle emission from ²³⁴Th.
  • The neutrons cannot be detected in this experiment because they have no electrical charge.

In Rutherford's experiment, the positive particles directed to the gold film were measured on a phosphorescent screen that with each arriving particle a luminous point is seen.

The particles in this experiment are α particles that have two positive charge and two no charged is a helium nucleus.

The test that can be carried out is to place a small ours of Thorium in front of a phosphorescent screen and see if it has flashes, with the amount of them we can determine the amount of particle emitted per unit of time.

Thorium has several isotopes, with different rates and types of emission:

  • ²³²Th emits α particles, it is the most abundant 99.9%
  • ²³⁴Th emits β particles, exists in small traces.

In this case they indicate that the material used is ²³⁴Th, which emits β particles that are electrons, the detection of these particles is more difficult since it has one negative charge, it has much lower mass, but they can travel further than the particles α, therefore, for what type of isotope we have, we can start measuring at a small distance and increase the distance until the reading is constant. At this point all the particles that arrive are β, which correspond to ²³⁴Th.

Neutron detection is much more difficult since these particles have no charge and therefore do not interact with electrons and no flashing on the screen is varied.

In conclusion with the characteristics of the α and β particles we can find the design of an experiment to measure the ²³⁴Th particles is:

  • On a screen, measure the emission as a function of distance and when the value reaches a constant, there is the β particle emission from ²³⁴Th.
  • The neutrons cannot be detected in this experiment because they have no electrical charge.

Learn more about radioactive emission here: brainly.com/question/15176980

7 0
3 years ago
If the hydrogen ion concentration is 10-7M, what is the pH of the solution?<br><br> Show all work.
Kobotan [32]
Remember pH=-log(H ions). So it would be pH=-log(10^-7).
6 0
4 years ago
Other questions:
  • A chemist prepares a solution of vanadium chloride by measuring out of into a volumetric flask and filling to the mark with dist
    8·2 answers
  • HELP ME PLEASE. Which of the following statements is true for electrolysis? New atoms are created by destroying old atoms. A com
    6·1 answer
  • A certain element exists as two different isotopes. 76.00% of its atoms have a mass of 35.00 amu and 24.00% of its atoms have a
    11·1 answer
  • The half-life of plutonium-239 is 24300. If a nuclear bomb released 8kg of this isotope, how many years would pass before the am
    10·1 answer
  • Determine the percent composition of potassium dichromate, K2Cr2O7.
    14·1 answer
  • What’s is a logical way that you could begin to investigate why your tire had low air pressure?
    13·1 answer
  • Q: If the average speed of a species of tortoise is 0.36 km/h, what is that speed in cm/s?
    13·1 answer
  • Touching a hot stove or the melting of ice in your hand (as you squeeze it) is an example of
    13·2 answers
  • how many grams of solid silver nitrate would you need to prepare 200.0 mL of a 0.150 M AgNO3 solution
    10·1 answer
  • Warm air masses tend to originate from:
    9·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!