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
Agata [3.3K]
3 years ago
7

Fiora starts riding her bike at 20 mi/h. After a while, she slows down to 14 mi/h, and maintains that speed for the rest of the

trip. The whole trip of 112 miles takes her 6.5 hours. For how long did she travel at 20 mi/h?
Physics
1 answer:
goblinko [34]3 years ago
4 0

Answer:

3.5 hours

Explanation:

Speed = distance/time

Let the distance that Fiora biked at 20 mi/h through be x miles and the time it took her to bike through that distance be t hours at 20 mi/h

Then, the rest of the distance that she biked at 14 mi/h is (112 - x) miles

And the time she spent biking at 14 mi/h the rest of the distance = (6.5 - t) hours

Her first biking speed = 20 mph = 20 miles/hour

Speed = distance/time

20 = x/t

x = 20 t (eqn 1)

Her second biking speed = 14 mph = 14 miles/hour

14 = (112 - x)/(6.5 - t)

112 - x = 14 (6.5 - t)

112 - x = 91 - 14t (eqn 2)

Substitute for x in (eqn 2)

112 - 20t = 91 - 14t

20t - 14t = 112 - 91

6t = 21

t = 3.5 hours

x = 20t = 20 × 3.5 = 70 miles.

(112 - x) = 112 - 70 = 42 miles

(6.5 - t) = 6.5 - 3.5 = 3 hours

Meaning that she travelled at 20 mi/h for 3.5 hours.

You might be interested in
Which equation correctly relates mechanical energy, thermal energy and total of energy when there is friction present in the sys
agasfer [191]

Answer:

E total = ME + E thermal

Explanation:

APEX

4 0
3 years ago
A stuntman jumps from the roof of a building to the safety net below. How far has the stuntman fallen after 1.6 seconds?
Fantom [35]
How tall is the building?
u need to divide the height by 1.6 to get your answer
6 0
3 years ago
The atom in the diagram has a neutral charge how many protons does it have
Olegator [25]

Explanation:

This should be of help:

An atom is made up of three subatomic particles:

  • Protons are the positively charged particles.
  • Electrons are the negatively charged particles.
  • Neutrons do not carry any charges.

A neutral atom is an atom that has not lost or gained any amount of electrons.

In a neutral atom;

                the number of protons and electrons are the same

 Usually atoms are designated this way:

                                                  ᵃₙX

  where X is the symbol of the atom

               a is the mass number of the atom

                n is the atomic number of the atom

 The mass number = number of protons + number of neutrons

        Atomic number = number of protons

Note; atomic number is the same as the number protons and the number of electrons in a neutral atom.

Use this guide to solve the problem

Learn more:

Atomic number brainly.com/question/5425825

#learnwithBrainly

8 0
4 years ago
A cool down is considered the activity performed
tangare [24]

did you mean what activities are performed during the cool down?

5 0
3 years ago
How to use unbalanced forces in a sentence
leva [86]
Forces occur in pairs and can be either balanced or unbalanced. Balanced forces do not cause a change in motion. Unbalanced Forces do cause a change in motion. 
4 0
3 years ago
Other questions:
  • A 400-g block of iron at 400°C is dropped into a calorimeter (of negligible heat capacity) containing 60 g of water at 30°C. How
    10·2 answers
  • Write a short description/summary of your chosen galaxy, and pose two questions you have about the galaxy. Post both your summar
    5·1 answer
  • Kathy tests her new sports car by racing with Stan, an experienced racer. Both start from rest, but Kathy leaves the starting li
    11·1 answer
  • A 2-kg cart, traveling on a horizontal air track with a speed of 3m/s, collides with a stationary 4-kg cart. The carts stick tog
    10·1 answer
  • Escape speed from the surface of earth is about
    6·2 answers
  • What is true of the moon's orbital and rotational periods?
    6·1 answer
  • Someone help pleaseee! serious answers only. how many miles are in 15,000 feet? 1 mile= 5,280 feet
    6·2 answers
  • What are 3 common sources of voltage difference?
    5·1 answer
  • Which describes the changes in visible light moving from red to violet?
    10·1 answer
  • After meeting the end the wave willa- reflect with larger amplitude.b- disappear.c- reflect with the same displacement. (not inv
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!