Answer: (a) 36.18mm
(b) 23.52
Explanation: see attachment
Answer:
The correct answer is option 'B': Load is far from fulcrum and the effort is applied near the fulcrum
Explanation:
A lever works on the principle of balancing of torques. The torque about the fulcrum by the load should be equal to the torque by the applied effort. Since we know that the torque is proportional to both the force and the distance it is applied from the distance from the axis of rotation. A lever is used when we need to lift a heavy load by utilizing this effect of the lever arm.
A mechanical disadvantage occurs when we are not able to lift the weight easily due to the fact we apply effort near the fulcrum.
Answer: 255
255 turns are required to create 25 ohms of secondary impedance.
Explanation:
Given that,
Number of turns in primary wire N₁ = 900
impedance on Primary wire Z₁ = 400 ohms
Number of turns in Secondary wire N₂ = ?
impedance on Secondary wire Z₂ = 25 ohms
we know that, the relationship between turn and impedance is
Zp / Zs = ( Np / Ns )²
(Primary impedance / secondary impedance) = Number of turns in primary wire / Number of turns in secondary wire)²
there fore
Z₁ / Z₂ = ( N₁ / N₂ )²
Now we substitute
( 400 / 25 ) = ( 900 / N₂ )²
400 / 25 = 900² / N₂²
we cross multiple to get our N₂
400 × N₂² = 900² × 25
N₂² = ( 900² × 25 ) / 400
N₂² = ( 810000 × 25 ) / 400
N₂² = 20250000 / 400
N₂² = 50625
N₂ = √50625
N₂ = 225
Therefore 255 turns are required to create 25 ohms of secondary impedance.
Answer:
a)R= sqrt( wt³/12wt)
b)R=sqrt(tw³/12wt)
c)R= sqrt ( wt³/12xcos45xwt)
Explanation:
Thickness = t
Width = w
Length od diagonal =sqrt (t² +w²)
Area of raectangle = A= tW
Radius of gyration= r= sqrt( I/A)
a)
Moment of inertia in the direction of thickness I = w t³/12
R= sqrt( wt³/12wt)
b)
Moment of inertia in the direction of width I = t w³/12
R=sqrt(tw³/12wt)
c)
Moment of inertia in the direction of diagonal I= (w t³/12)cos 45=( wt³/12)x 1/sqrt (2)
R= sqrt ( wt³/12xcos45xwt)
