Answer:
C. 72
Explanation:
Transformer: A transformer is an electromagnetic device that uses the property of mutual inductance to change the voltage of alternating supply.
In a ideal transformer,
Vs/Vp = Ns/Np ............................................. Equation 1
Where Vp = primary voltage, Vs = secondary voltage, Ns = Secondary turn, Np = primary turn.
Making Ns the subject of the equation,
Ns =(Vs/Vp)Np .......................................... Equation 2
Given: Vs = 24 V, Vp = 115 V, Np = 345.
Substitute into equation 2
Ns = (24/115)345
Ns = 72 turns.
Thus the number of turns in the secondary = 72 turns.
The right option is C. 72
Answer:
v = 7671.57 m/s
T = 1.55 hours
Explanation:
mass of Earth, M = 6 x 10^24 kg
Radius of earth, R = 6400 km = 6.4 x 10^6 m
height, h = 400 km
Velocity is given by
where, G be the universal gravitational constant.
G = 6.657 x 10^-11 Nm^2/kg^2
v = 7671.57 m/s
Let T b the period
T = 5566.53 second
T = 1.55 hours
Answer:
0.0327 m
Explanation:
m = 2 kg
ω = 24 rad/s
A = 0.040 m
Let at position y, the potential energy is twice the kinetic energy.
The potential energy is given by
U = 1/2 m x ω² x y²
The kinetic energy is given by
K = 1/2 m x ω² x (A² - y²)
Equate both the energies as according to the question
1/2 m x ω² x y² = 2 x 1/2 m x ω² x (A² - y²)
y² = 2 A² - 2 y²
3y² = 2A²
y² = 2/3 A²
y = 0.82 A = 0.82 x 0.040 = 0.0327 m
The answer is true because the invention ofthe beto
Answer:
4.2 m
Explanation:
Note: If energy is conserved, i.e no work is done against friction
Work input = work output.
Work output = Force output × distance,
Work input = force input × distance moved moved.
Therefore,
input force×distance moved = output force × distance moved........................Equation 1
Given: input force = 80 N, output force = 240 N, output distance = 1.4 m
Let input distance = d
Substitute into equation 1
80×d = 240×1.4
80d = 336
d = 336/80
d = 4.2 m.
Thus the rope around the pulley must be pulled 4.2 m
