NaHCO3
That is the formula for baking soda
Answer:
67
Explanation:
- The atomic number (Z) of an atom is equal to the number of protons in the nucleus
- The mass number (A) of an atom is equal to the sum of protons and neutrons in the nucleus
Therefore, calling p the number of protons and n the number of neutrons, for element X we have:
Z = p = 23
A = p + n = 90
Substituting p=23 into the second equation, we find the number of neutrons:
n = 90 - p = 90 - 23 = 67
Answer:
ω = 380π rad/s
Explanation:
The formula for the angular frequency is the oscillation frequency f (hertz) multiplied by 2π
ω = 2πf
then
ω = 2π(190)
ω = 380π rad/s
Answer:

Explanation:
<u>Accelerated Motion
</u>
When a body changes its speed at a constant rate, i.e. same changes take same times, then it has a constant acceleration. The acceleration can be positive or negative. In the first case, the speed increases, and in the second time, the speed lowers until it eventually stops. The equation for the speed vf at any time t is given by

where a is the acceleration, and vo is the initial speed
.
The train has two different types of motion. It first starts from rest and has a constant acceleration of
for 182 seconds. Then it brakes with a constant acceleration of
until it comes to a stop. We need to find the total distance traveled.
The equation for the distance is

Our data is

Let's compute the first distance X1


Now, we find the speed at the end of the first period of time


That is the speed the train is at the moment it starts to brake. We need to compute the time needed to stop the train, that is, to make vf=0



Computing the second distance


The total distance is


