Answer:
Explanation:
N=Rotor Speed in Revolution per minute(rpm)
for P=4 and N=3600, f comes out to be 120 Hz.
So frequency of voltage produced is 120 Hz. But this is not practical. Generally 4-Pole generator has N=1500rpm(for 50 Hz) or 1800rpm for 60 Hz. Two pole generator can have N=3600rpm(f=60Hz).
The most practical situation is generator having N=3600Hz with 2 Poles.
Hope It will be helpful!!!
In other words a infinitesimal segment dV caries the charge
<span>dQ = ρ dV </span>
<span>Let dV be a spherical shell between between r and (r + dr): </span>
<span>dV = (4π/3)·( (r + dr)² - r³ ) </span>
<span>= (4π/3)·( r³ + 3·r²·dr + 3·r·(dr)² + /dr)³ - r³ ) </span>
<span>= (4π/3)·( 3·r²·dr + 3·r·(dr)² + /dr)³ ) </span>
<span>drop higher order terms </span>
<span>= 4·π·r²·dr </span>
<span>To get total charge integrate over the whole volume of your object, i.e. </span>
<span>from ri to ra: </span>
<span>Q = ∫ dQ = ∫ ρ dV </span>
<span>= ∫ri→ra { (b/r)·4·π·r² } dr </span>
<span>= ∫ri→ra { 4·π·b·r } dr </span>
<span>= 2·π·b·( ra² - ri² ) </span>
<span>With given parameters: </span>
<span>Q = 2·π · 3µC/m²·( (6cm)² - (4cm)² ) </span>
<span>= 2·π · 3×10⁻⁶C/m²·( (6×10⁻²m)² - (4×10⁻²m)² ) </span>
<span>= 3.77×10⁻⁸C </span>
<span>= 37.7nC</span>
Answer:
B: 1530 N
Explanation:
We know ghat formula for force of gravity is;
F_grav = G•m1•m2/d²
We are told that two clay masses produce a gravitational force of 340N.
Thus;
G•m1•m2/d² = 340
Now, if the distance is divided by 3 and the mass of one is divided by 2, we have;
F_g = (G × m1/2 × m2)/(d/3)²
Thus gives;
F_g = ½(G•m1•m2)/((1/9)d²)
Simplifying this gives;
F_g = (9/2)G•m1•m2/d²
From earlier, we saw that;
G•m1•m2/d² = 340
Thus;
F_g = (9/2) × 340
F_g = 1530 N
Answer:
B. 34.78 m/s
Explanation:
Momentum of a body or an object is given as the product of its velocity and its mass.
Therefore;
Momentum= velocity x mass
But; velocity = ? mass =115 kg , momentum = 4,000 kgm/s
Thus; velocity= momentum/mass
= 4,000/115
= 34.78 m/s
Mass is scalar physical quantity wich is measured by kg. and only expressed by its magnitude