All categories

3 years ago

Why aren't the electrons counted in the mass of an atom?

Physics

1 answer:

Radda [10]3 years ago

3 0

Answer:

Explanation:

The mass of an electron is small compared to the neutron and proton, so it's negligible. It's like adding zero to a number.

You might be interested in

Please help important 100 point science quiz!

Norma-Jean [14]

Answer: The answer is C

Explanation:

8 0

3 years ago

Predict whether the changes in enthalpy, entropy, and free energy will be positive or negative for the melting of ice, and expla

BlackZzzverrR [31]

Melting of ice is an endothermic process, meaning that energy is absorbed. When ice spontaneously melts, ΔH (change in enthalpy) is "positive". ΔS (entropy change) is also positive, because, becoming a liquid, water molecules lose their fixed position in the ice crystal, and become more disorganized. ΔG (free energy of reaction) is negative when a reaction proceeds spontaneously, as it happens in this case. Ice spontaneously melts at temperatures higher than 0°C. However, liquid water also spontaneously freezes at temperatures below 0°C. Therefore the temperature is instrumental in determining which "melting" of ice, or "freezing" of water becomes spontaneous. The whole process is summarized in the Gibbs free energy equation:
ΔG = ΔH – TΔS

4 0

3 years ago

An elevator is moving downward when someone presses the emergency stop button. The elevator comes to rest a short time later. Gi

OLga [1]

Answer:

Answer: - , +

Explanation:

Velocity and Acceleration

In general terms, velocity and acceleration in the plane are both vectors with two components. They don't have 'sign' but magnitude and direction. If we know motion is restricted to a simple line, then we can define the positive and negative references.

In vertical motion, the positive reference is commonly pointed upwards, but if we chose the opposite way, the results shouldn't change in magnitude, just their signs. Let's choose like proposed, the positive direction upwards.

Since the elevator was moving downwards, its velocity is negative. When the button is pushed, it continues to move downwards, but slower. Its velocity is still negative.

The acceleration has the same sign as the velocity if it tends to increase the magnitude of the object, and is negative in the opposite case. Let's look at the formula

$\displaystyle a=\frac{v_f-v_o}{t}$

In this case, $v_f=0$ because the elevator will eventually stop, and $v_o$ is negative. It means the acceleration is

$\displaystyle a=\frac{-v_o}{t}$

It results in a positive value

$\boxed{Answer: -,+}$

Note: If we chose the opposite references, then the answer would be: +,-

5 0

3 years ago

Imagine you derive the following expression by analyzing the physics of a particular system: v2=v20+2ax. The problem requires so

lisabon 2012 [21]

As per kinematics equation we are given that

$v^2 = v_o^2 + 2ax$

now we are given that

a = 2.55 m/s^2

$v_0 = 21.8 m/s$

$v = 0$

now we need to find x

from above equation we have

$0^2 = 21.8^2 + 2(2.55)x$

$0 = 475.24 + 5.1 x$

$x = 93.2 m$

so it will cover a distance of 93.2 m

7 0

3 years ago

Read 2 more answers

Why is the horizontal component of a velocity remains constant in horizontal and inclined projection

lesya692 [45]

Answer:

The force of gravity does not affect the horizontal component of motion; a projectile maintains a constant horizontal velocity since there are no horizontal forces acting upon it.

8 0

3 years ago