1. Answer:
It allows scientists to predict things about objects that are too small to see.
Explanation:
Atomic models are crucial to the scientific study of atoms. Through models, we represent atoms that we actually cannot see. Observation based study and testing is done through that model which helps us find flaws in one model so that a better model is made. In this way, it is helpful to study about atoms through atomic models.
2. Answer:
The correct step in a scientific experiment involving acids and bases is:
Using an indicator to measure the hydrogen ion concentration of a solution.
Explanation:
Two acids can never neutralize each other. The pH of a neutral solution is 7. Whereas pH of an acid is always less than 7.
Indicators are used to measure the pH of solutions. They give different colors in solutions with different solutions. So, in an experiment to check if the solution is acidic or basic, we need to measure its hydrogen ion concentration for which an indicator is used.
Hope I helped! Brainiest plz! Hope you make an 100% and have a wonderful day! -Amelia♥
Answer:
The thrust of the jet engine is 4188.81 N.
Explanation:
Given that,
Speed = 260 m/s
Rate in air= 53.3 kg/s
Rate of fuel = 3.63 kg/s
Relative speed = 317 m/s
We need to calculate the rate of mass change in the rocket
Using formula of rate of mass
![\dfrac{dM}{dt}=\dfrac{dM_{a}}{dt}+\dfrac{dM_{f}}{dt}](https://tex.z-dn.net/?f=%5Cdfrac%7BdM%7D%7Bdt%7D%3D%5Cdfrac%7BdM_%7Ba%7D%7D%7Bdt%7D%2B%5Cdfrac%7BdM_%7Bf%7D%7D%7Bdt%7D)
Put the value into the formula
![\dfrac{dM}{dt}=53.3+3.63](https://tex.z-dn.net/?f=%5Cdfrac%7BdM%7D%7Bdt%7D%3D53.3%2B3.63)
![\dfrac{dM}{dt}=56.93\ kg/s](https://tex.z-dn.net/?f=%5Cdfrac%7BdM%7D%7Bdt%7D%3D56.93%5C%20kg%2Fs)
We need to calculate the thrust of the jet engine
Using formula of thrust
![T=\dfrac{dM}{dt}u-\dfrac{dM_{a}}{dt}v](https://tex.z-dn.net/?f=T%3D%5Cdfrac%7BdM%7D%7Bdt%7Du-%5Cdfrac%7BdM_%7Ba%7D%7D%7Bdt%7Dv)
Put the value into the formula
![T=56.93\times317-53.3\times260](https://tex.z-dn.net/?f=T%3D56.93%5Ctimes317-53.3%5Ctimes260)
![T=4188.81\ N](https://tex.z-dn.net/?f=T%3D4188.81%5C%20N)
Hence, The thrust of the jet engine is 4188.81 N.
<span>Speed of the sphere = 7 m/s
Distance between center of the circle to the center of the sphere = 1.8 m
Mass of the sphere = 6kg
Radius of the sphere = 0.89 m
Angular speed w = 5.62
Rotational kinetic energy of the sphere = 1/2 I x w^2
I being the moment of inertia, w being the angular speed
I = (2/5) x M x R^2 = (2/5) x 6 x 0.89^2 = 1.90
Rotational kinetic energy = 1/2 x 1.9 x 5.62^2 = 30 J</span>
true very true in my past 2 and a half years in high school I say it is true