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
marshall27 [118]
3 years ago
9

. The average human walks at a speed of 5 km per hour. If your PE teacher asks you to walk for 30 minutes in

Physics
1 answer:
lisabon 2012 [21]3 years ago
7 0

Answer: 2.5 km

Explanation:

5/2 = 2.5 km

60/2 = 30 mins

You might be interested in
A gas is compressed from 600cm3 to 200cm3 at a constant pressure of 450kPa . At the same time, 100J of heat energy is transferre
Paraphin [41]

Answer: 80J

Explanation:

According to the first principle of thermodynamics:  

<em>"Energy is not created, nor destroyed, but it is conserved."  </em>

Then this priciple (also called Law) relates the work and the transferred heat exchanged in a system through the internal energy U, which is neither created nor destroyed, it is only transformed. So, in this especific case of the compressed gas:

\Delta U=Q+W  (1)

Where:

\Delta U is the variation in the internal (thermal) energy of the system (the value we want to find)

Q=-100J is the heat transferred out of the gas (that is why it is negative)

W is the work is done on the gas (as the gas is compressed, the work done on the gas must be considered positive )

On the other hand, the work done on the gas is given by:

W=-P \Delta V  (2)

Where:

P=450kPa=450(10)^{3}Pa is the constant pressure of the gas

\Delta V=V_{f}-V_{i} is the variation in volume of the gas

In this case the initial volume is V_{i}=600{cm}^{3}=600(10)^{-6}m^{3} and the final volume is V_{f}=200{cm}^{3}=200(10)^{-6}m^{3}.

This means:

\Delta V=200(10)^{-6}m^{3}-600(10)^{-6}m^{3}=-400(10)^{-6}m^{3}  (3)

Substituting (3) in (2):

W=-450(10)^{3}Pa(-400(10)^{-6}m^{3})  (4)

W=180J  (5)

Substituting (5) in (1):

\Delta U=-100J+180J  (6)

Finally:

\Delta U=80J  This is the change in thermal energy in the compression process.

8 0
3 years ago
Share your thoughts about this statement by John Wesley<br> "Electricty is the soul of universe"
ikadub [295]

Answer:

<em>I think this statement is true at least in modern day times. The world runs on nothing but technology. People use more technology instead of old school textbooks and papers. Imagine living in a world without technology… that means no cars, no trains, no devices, no machines like your stove or printer, no lights and lots more. John Wesley is 100 percent correct with this statement. Electricity is indeed the powerhouse of the universe. </em>

4 0
3 years ago
Read 2 more answers
how does the composition of a mixture of hydrogen and oxygen differ of hydrogen and oxygen differ from the composition of a comp
mafiozo [28]
In a mixture, there will be a solute and solvent. The hydrogen and oxygen are still two different atoms that just mixed together. But in a compound, the hydrogen and oxygen have a bond, making a new and bigger molecule. A mixture can easily be separated by physical means but a compound isn't.
6 0
3 years ago
Why is water pollution a concern if water is continuously cycled through Earth’s systems?
kati45 [8]

Answer:Water pollution is a concern because since it is cycled threw the earths system it effect the earths system in a negative way.

Explanation:

I would wait for someone else to answer just in case I’m wrong.

7 0
3 years ago
If the action force is a player kicking a soccer ball, then what is the reaction force?
LiRa [457]
The force acting on his feet.
4 0
3 years ago
Other questions:
  • Since illness can be caused by bacteria that live in water, pollution in water can lead to serious illness. true or false
    8·1 answer
  • Which parts of a compound microscope magnify objects? a convex and a concave lens two convex lenses two concave lenses one conca
    9·2 answers
  • The most common type of dam is an impoundment hydroelectric plant, which consists of a dam across a river, and a reservoir (lake
    7·1 answer
  • Why is an iron core needed in an electromagnet?
    14·1 answer
  • 10. A skydiver falls with acceleration due to gravity of 9.81 mlsls.
    6·1 answer
  • What does sound need to travel?​
    12·2 answers
  • Rice in a bowl has a volume of 84 cubic centimeters and a mass of 63 grams . Calculate its destiny
    13·2 answers
  • WA
    14·1 answer
  • SKILL LEVEL:
    5·1 answer
  • A gas at 110atm and 303K filled a container of 2L. If the temperature is raised to 353 K and the pressure is increased to 440atm
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!