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
labwork [276]
3 years ago
10

An airplane flies 21 km in 30 minutes. What is its average speed in kilometers per hour?

Physics
2 answers:
Katena32 [7]3 years ago
8 0

Average speed = (distance covered) / (time to cover the distance)

Average speed = (21 km) / (1/2 hour)

Average speed = (21/0.5) (km/hour)

Average speed = 42 km/hr

A very slow airplane !  Maybe an ultralight, a motorized hang-glider, etc.

Citrus2011 [14]3 years ago
7 0
30 minutes is 1/2 of an hour.

So if you just multiplied 21×2, you would get you answer.
The answer is:
42 kilometers per hour
You might be interested in
Given one mole of diamond vs one mole of graphite,
grandymaker [24]

Answer:

The pressure is P= -  6.39*10^8Pa

The temperature is T =1218.63 K

Explanation:

Generally Gibbs free energy is mathematically represented as

                   G = E + PV -TS

   Where  E is the enthalpy

               PV is the pressure volume energy (i.e PV energy)

                S  is the entropy

                T is the temperature

For stability to occur the Gibbs free energy must be equal to zero

Considering Diamond

  So at temperature of  T = 300 K

         E + PV - TS = 0

making P the subject

          P = \frac{TS-E}{V}

Now substituting 300 K for T , 2900 J  for E ,

                              3.42cm^3 = \frac{3.42}{1*10^6} = 3.42*10^{-6}m^3 for V and 2.38 J/K for S

     P = \frac{(300 * 2.38)- 2900}{3.42*10^{-6}}

         P= -  6.39*10^8Pa

The negative sign signifies the direction of the pressure

Given that  P = 1*0^5Pa

making T the subject

            T = \frac{PV+E}{S}

Substituting into the equation

            T = \frac{1*10^5 * 3.42 *10^{-6}+2900}{2.38}

                T =1218.63 K

             

         

7 0
3 years ago
Read 2 more answers
Help hurry help pls it’s timed
Jobisdone [24]

Answer:

its the teal/second from the left one

Explanation:

4 0
3 years ago
Read 2 more answers
Why are jovian planets so much larger than terrestrial planets?
Nataly [62]

Explanation:

The temperature in the inner solar system was too high for light gases to condense, while in the outer solar system, the temperature was much lower, which allowed the Jovian planets to form, which grew enough to accumulate and retain the hydrogen gas that remained in the solar nebula, which led to its high levels of hydrogen and large size.

7 0
3 years ago
How much time will it take for a bug to travel 2 meters across the floor if it is traveling at 0.5 m/s?
7nadin3 [17]
4 seconds to travel 2 meters :)
6 0
3 years ago
What is the product of mass and velocity called?
Crank
The product of mass and velocity is momentum. P=mv. The 'P' in the equation stands for momentum.
3 0
3 years ago
Other questions:
  • how can the thumb and fingers of your right hand be used to identify the direction of a magnetic field?
    11·1 answer
  • You are driving to the grocery store at 18 m/s. You are 120 m from an intersection when the traffic light turns red. Assume that
    9·1 answer
  • A ball is whirled on the end of a string in a horizontal circle of radius R at a speed v. Complete the following statement: The
    15·2 answers
  • What is the level of incidence
    5·1 answer
  • When hydrogen is heated or subjected to an electric discharge, it emits light with specific visible wavelengths. A diffraction g
    6·1 answer
  • How many simple machines are in a wine opener? The kind with the bottle opener at the head and two "arms."
    8·2 answers
  • A match is being is an example of
    9·1 answer
  • Help please ill give brainly and heart !!!!
    8·2 answers
  • Why is it important that we learn about our solar system, the sun, and planets in our solar system other than Earth?
    6·1 answer
  • What happened to the balloon when it was placed on the bottle with the baking soda and vinegar and why
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!