C, electrons are negative, and most of the atom’s mass comes from the nucleus of the atom
Answer:
Explanation:
Given that,
Mass of ball m = 2kg
Ball traveling a radius of r1= 1m.
Speed of ball is Vb = 2m/s
Attached cord pulled down at a speed of Vr = 0.5m/s
Final speed V = 4m/s
Let find the transverse component of the final speed using
V² = Vr²+ Vθ²
4² = 0.5² + Vθ²
Vθ² = 4²—0.5²
Vθ² = 15.75
Vθ =√15.75
Vθ = 3.97 m/s.
Using the conservation of angular momentum,
(HA)1 = (HA)2
Mb • Vb • r1 = Mb • Vθ • r2
Mb cancels out
Vb • r1 = Vθ • r2
2 × 1 = 3.97 × r2
r2 = 2/3.97
r2 = 0.504m
The distance r2 to the hole for the ball to reach a maximum speed of 4m/s is 0.504m
The required time,
Using equation of motion
V = ∆r/t
Then,
t = ∆r/Vr
t = (r1—r2) / Vr
t = (1—0.504) / 0.5
t = 0.496/0.5
t = 0.992 second
A gas heated to millions of degrees would emit mostly x-rays.
If a surface looks "shiny" to you, that's because it reflects all
or most of the visible light that hits it. That doesn't always mean
that the same surface reflects other, non-visible wavelengths of
light. Infrared radiation may also reflect off of it, and probably
does. But you can't be sure just because it's visibly shiny.
Answer:
Explanation:
Given that:
the initial angular velocity 
angular acceleration 
= 4.44 rad/s²
Using the formula:
Making t the subject of the formula:
where;
∴
t = 0.345 s
b)
Using the formula:
here;
= angular displacement
∴
Recall that:
2π rad = 1 revolution
Then;
0.264 rad = (x) revolution
x = 0.042 revolutions
c)
Here; force = 270 N
radius = 1.20 m
The torque = F * r
However;
From the moment of inertia;
given that;
I = 84.4 kg.m²
For re-tardation; 
Using the equation
t = 0.398s
The required time it takes= 0.398s
