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3 years ago

If the atomic number of an atom is 4 and the mass number is 9, then how many electrons does it have

1 answer:

5 0

The atomic number of an atom says how many protons it has. This number cant change, since the atomic number is what gives elements their identities (in the periodic table, at least).
The mass number, on the other hand, says how many protons AND neutrons the atom has (so, the sum of P+ and N0). So, electrons have nothing to do with this number.
Atoms are neutrally charged, which means there has to be an equal number of positive and negative particles. The negative particles of an atom are its electrons, and since our atom has 4 protons, it must also have 4 electrons.

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____ is the force that moves people to behave, think, and feel the way they do, resulting in behavior that is energized, directe

pogonyaev

Answer:

Motivation

Explanation:

Motivation is the force that directs one's behavior. This force is required for repeated actions. There are two types of motivation:

Intrinsic

This type of motivation is comes from the individual

Extrinsic

This type of motivation is comes from an external influence.

Both conscious and unconscious factors influence motivation.

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3 years ago

Match the following vocabulary words with their definitions:

Ronch [10]

Correct matching:

1 acceleration --> rate of change in velocity, which is the change in velocity divided by the change in time

2. speed --> the rate at which an object changes position when traveling in a certain direction

4. gravity --> force of attraction between all masses in the universe

5. Inertia --> an object´s resistance to a change in motion

3. friction --> force of resistance acting between objects in contact and tending to dampen their motion

6. velocity --> the rate at which an object changes position

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3 years ago

Please help me with the equations for this! Three uniform spheres are fixed at the positions shown in the diagram. ( there is a

lora16 [44]

The change in gravitational potential energy due to change in position must be the change in it's kinetic energy as the system is isolated! so find out the potential energies of the two different points!

PE=−[GM1M2]÷R

 Potential energy of a particle due to mass A is not affected by presence of any other mass B !

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3 years ago

11. Trait theory claims that

svetoff [14.1K]

A. people from the same location share the same personality type.

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2 years ago

Which is not expecting acceleration?

Kamila [148]

1. Answer: A skydiver whose air resistance is equal to that of her weight.

A skydiver free falls under gravity but her rate of fall slows down due to drag -air resistance. when this air resistance becomes equal to her weight, the two get balanced and the body does not accelerate or decelerates.

2. Answer: Gravity

Contact forces are those which act when there is physical contact between two bodies. For example: normal force, tension and spring force.

Non-contact forces act between two bodies even when they are at a distance apart. For example: gravity, electric force, magnetic force etc.

3. Answer: The tendency of an object's motion to remain the same.

Inertia is a property of matter by virtue of which it tends to remain in its state of motion or rest. It does depend on mass of the object, more the mass, more is inertia. For example, cycle can be easily moved but we need real push hard for a car to move.

4. Answer: 254 N

The man pushes the box with 310 N force at an angle of 55 degrees to the horizontal.

we can write this in terms of horizontal ( $F cos \theta$ )and vertical component ( $F sin\theta$ ).

Horizontal component: $F_H=310 \times cos (55^o)= 178 N$

Vertical component: $F_v=310 \times sin (55^o)= 254 N$

The vertical component would act towards the floor making the job more difficult to move the job.

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3 years ago