Answer:
Explanation:
It is given that,
Mass of the grindstone, m = 3 kg
Radius of the grindstone, r = 8 cm = 0.08 m
Initial speed of the grindstone, 
Finally it shuts off, 
Time taken, t = 10 s
Let 
is the angular acceleration of the grindstone. Using the formula of rotational kinematics as :
Let 
is the number of revolutions of the grindstone after the power is shut off. Now using the third equation of rotational kinematics as :
or
So, the number of revolutions of the grindstone after the power is shut off is 50.
Answer:
Explanation:
Tarzan swing can be thought of as change in potential energy by going from higher location We solve for height of beginning of the swing by using simple cosine equation:
So
ΔE=mg(h₂-h₁)
The potential energy of Tarzan initial position is converted into kinetic energy of his swing.By using kinetic equation
Answer:
Quark
Explanation:
In the past the proton,neutron and electron were believed to be indivisible. Quarks were later discovered to be particles that make up the proton and neutron. Quarks are known as fast moving points of energy and are usually joined to one another through gluons. Neutron has two down quarks and one up quark while proton has two up quarks and one down quark.
Explanation:
The 11Ω, 22Ω, and 33Ω resistors are in parallel. That combination is in series with the 4Ω and 10Ω resistors.
The net resistance is:
R = 4Ω + 10Ω + 1/(1/11Ω + 1/22Ω + 1/33Ω)
R = 20Ω
Using Ohm's law, we can find the current going through the 4Ω and 10Ω resistors:
V = IR
120 V = I (20Ω)
I = 6 A
So the voltage drops are:
V = (4Ω) (6A) = 24 V
V = (10Ω) (6A) = 60 V
That means the voltage drop across the 11Ω, 22Ω, and 33Ω resistors is:
V = 120 V − 24 V − 60 V
V = 36 V
So the currents are:
I = 36 V / 11 Ω = 3.27 A
I = 36 V / 22 Ω = 1.64 A
I = 36 V / 33 Ω = 1.09 A
If we wanted to, we could also show this using Kirchhoff's laws.
They have thick body coverings
