Answer:
Time, t = 0.015 seconds.
Explanation:
Given the following data;
Mass, m = 0.2kg
Force, F = 200N
Initial velocity, u = 40m/s
Final velocity, v = 25m/s
To find the time;
Ft = m(v - u)
Time, t = m(v - u)/f
Substituting into the equation, we have;
Time, t = 0.2(25 - 40)/200
Time, t = 0.2(-15)/200
Time, t = 3/200
Time, t = 0.015 seconds.
Note: We ignored the negative sign because time can't be negative.
Once the atomic number of an atom is known, the number of electrons can be deduced depending on if the atom is an ion or a neutral one.
<h3>Atomic number</h3>
The atomic number of an atom is the number of protons in the nucleus of the atom.
For atoms that are neutral, that is, no net charges, the number of protons is always equal to the number of electrons. In other words, the positive charges always balance the negative charges in neutral atoms.
Thus, if the atomic number of a neutral atom is 6, for example, the proton number will also be 6. Since the proton must balance the electron, the number of electrons will also be 6.
More on atomic numbers can be found here; brainly.com/question/17274608
Answer:
<h2>What are we supposed to write about</h2>
Explanation:
Answer:
Option B, two walls and the floor
Explanation:
The distance should be measured from the point where at least the three axed meet.
Two walls and the floor are equivalent to three axes.
Vertical wall 1 = Y Axis
Horizontal wall2 = X Axis
Floor = Z Axis
Thus, the distance should be measured from the point where two walls and one floor meet.
Option , B is correct
Answer:
a)- 1.799 rad/sec²
b)- 17.6 x 10ˉ³Nm
Explanation:
ω₀ = 720 rev/min x (1 min/60 sec) x (2π rad / 1 rev) = 24π rad/s
a) Assuming a constant angular acceleration, the formula will be
α = (ωf -ω₀) / t
As final state of the grindstone is at rest, so ωf =0
⇒ α = (0-24π) / 41.9 = - 1.799 rad/sec²
b)Moment of inertia I for a disk about its central axis
I = ½mr²
where m=2kg and radius 'r'= 0.099m
I = ½(2)(0.099²)
I = 9.8 x 10ˉ³ kgm²
Next is to determine the frictional torque exerted on the grindstone, that caused it to stop, applying the rotational equivalent of the Newton's 2nd law:
τ = I α =>(9.8 x 10ˉ³)(- 1.799)
τ = - 17.6 x 10ˉ³Nm
(The negative sign indicates that the frictional torque opposes to the rotation of the grindstone).
