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
adoni [48]
3 years ago
6

You drive to the city at an average speed of 40 km/h and return at an average speed of 60 km/h. Find your average speed for the

entire trip? Explain why the answer is not 50 km/h.
Physics
1 answer:
Eva8 [605]3 years ago
7 0
Well, let's see:

If you live 'D' kilometers from the city, and you go and return by the same route, then

-- The time it takes you to reach the city, at 40 km/h, is  D/40  hours.

-- The time it takes you to return, at 60 km/h, is    D/60.

-- The total distance you cover is  2D, and the total driving time is

                        (D/40) + (D/60)

                   =  (3D/120)  +  (2D/120)

                   =        5D/120  =  D/24

-- Your average speed for the entire trip is

                         (distance covered)  /  (time to cover the distance)

                   =            ( 2D )   /   ( D/24 )

                   =              48 km/hr.  

You might be interested in
With which of the following statements would Whorf and Sapir agree?
ASHA 777 [7]
Hi!

The answer is <span>B. Language influences how people understand their world.

Hope this helps!

-Payshence xoxo</span>
6 0
2 years ago
Read 2 more answers
How does frequency relate to pitch?
tensa zangetsu [6.8K]
The sensation of a frequency is commonly referred to as the pitch of a sound. A high pitch sound corresponds to a high frequency sound wave and a low pitch sound corresponds to a low frequency sound wave. ... That is, two sound waves sound good when played together if one sound has twice the frequency of the other.
7 0
2 years ago
An automobile having a mass of 1,000 kg is driven into a brick wall in a safety test. The bumper behaves like a spring with cons
vlada-n [284]

Answer:

v=2.02\frac{m}{s}

Explanation:

Assuming no energy lost, according to the law of conservation of energy, the kinetic energy of the automobile becomes potential energy after the crash:

K=U\\\frac{mv^2}{2}=\frac{kx^2}{2}

Here m is the automobile's mass, v is the speed of the car before impact, k is the "bumper" constant and x is the compression of the bumper due to the collision. Solving for v:

v=x\sqrt\frac{k}{m}\\v=2.63*10^{-2}m\sqrt{\frac{5.9*10^6\frac{N}{m}}{10^3kg}}\\v=2.02\frac{m}{s}

8 0
3 years ago
What are food source of calcium?
bearhunter [10]

Answer:

Milk

Explanation:

It can be milk and other foods similar to milk like ice cream, cheese, yogurt, etc. This is why people say milk is good for your bones cause it has calcium

5 0
3 years ago
Read 2 more answers
Under certain circumstances, potassium ions (K+) in a cell will move across the cell membrane from the inside to the outside. Th
choli [55]

Answer:

1.368\times 10^{-20}\ J

Explanation:

q = Charge in the potassium ion = 19e-18e

e = Charge of electron = 1.6\times 10^{-19}\ C

V_2-V_1 = Change in potential = 0-(-85.5\times 10^{-3})

Change in electric potential is given by

E=q(V_2-V_1)\\\Rightarrow E=(19e-18e)(0-(-85.5\times 10^{-3})\\\Rightarrow E=1.6\times 10^{-19}\times 85.5\times 10^{-3}\\\Rightarrow E=1.368\times 10^{-20}\ J

The energy is 1.368\times 10^{-20}\ J

3 0
3 years ago
Other questions:
  • Relative velocity.....Please help....​
    6·1 answer
  • What is the difference between the states of phase equilibrium and metastability?
    12·1 answer
  • Halving the distance (i.e., decreasing by a factor of two) between two charged objects will cause the electrical force between t
    8·1 answer
  • a 100 kg gymnast comes to a stop after tumbling. her feet do -5000J of net work to stop her. Use the work-kinetic energy theorem
    10·2 answers
  • The fastest possible conduction velocity of action potentials is observed in ________.
    7·1 answer
  • A bullet travels at 850 m/s. how long will it take a bullet to go 1 km?
    11·1 answer
  • A person tosses a ball from the ground up into the air at an initial speed of 10 m/sec and an initial angle of 43◦ off the groun
    8·1 answer
  • Which number below equals 129000? * *
    11·1 answer
  • 10. A boy weighs 475 N. What is his mass? (acceleration due to gravity on Earth is 9.8m/s2 = g)
    10·1 answer
  • 3.
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!