Answer:
positive
An atom has a even amount of protons, electrons, and a little less neutrons. If the atom lost one electron, then it now has a positive charge.
Hope it helps!
Answer:
Option (a)
Explanation:
Given that,
Mass of a car, m = 1200 kg
Force exerted by the engine, F = 600 N
Noe force,F = ma
a is the acceleration of the engine

So, the acceleration of the car is 0.5 m/s².
Classics.
Resistance is equal to relation between voltage and current.

If we express current:

If current is in fact 0 then one of the quantities either voltage or resistance must be equal to zero. Since resistance cannot be equal 0, because that would violate mathematical law that states that division by zero is undefined the only logical conclusion is voltage.
So the answer should be C voltage and B zero.
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Answer:
The emission spectrum is always the same and can be used to identify the element and part of the Bohr model proposed that electrons in the hydrogen are located in particular orbits around the nucleos are True.
Explanation:
The Niels Bohr and quantic mecanic theorys are both based on the study of atomics spectrums. The atomic spectrum is a characteristic pattern of a light wavelenght emited wich is unique to each element.
<u>For example</u>, if we put some low pressure hydrogen in a glass tube and in the tp of the glass we apply a voltage big enough to produce a electric current in the hydrogen gas, the tube its going to emit light wich have a color dependig of the gas element in the interior. If we observe this light with a spectrometer we are going to see shining lines and each one of this lines have a wavelenght and diferent colors. This lines are called emission spectrum and the wavelength of that spectrum are unique to eache element.
<u>Summering up, </u>we can identify elements using the emission spectrum because any element produces the same spectrum than other element.
According to Niels Bhor theory the electron only can be in especific discret ratios to the nucleus. Where this electron moves himself in circukar orbits under the influence of the Coulomb attraction force.
A) Calling F the intensity of the horizontal force and d the displacement of the block across the floor, the work done by the horizontal force is equal to

b) The work done by the frictional force against the motion of the block is equal to:


Part of these 105.1 Joules of work becomes increase of thermal energy of the block (

), and part of it becomes increase of thermal energy of the floor (

). We already know the increase in thermal energy of the block (38.2 J), so we can find the increase in thermal energy of the floor:

c) The net work done on the block is the work done by the horizontal force F minus the work done by the frictional force (the frictional force acts against the motion, so we must take it with a negative sign):

For the work-energy theorem, the work done on the block is equal to its increase of kinetic energy:

So, we have