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yaroslaw [1]
3 years ago
8

A weightlifter is attempting a biceps curl with a 200 n barbell. the moment arm of the barbell about the elbow joint is 40 cm. t

he moment arm of the elbow flexor muscles is 4 cm. how much force must be produced by these muscles to hold the 200 n barbell in static equilibrium?
Physics
1 answer:
CaHeK987 [17]3 years ago
4 0
Weight of the barbell W = 200 Ndistance of the joint is r = 40 cm = 0.4 mtorque created by the weight at the joint is                  τ = F*r                     = 200 N*0.4 m                     = 80 N.mat equilibrium condition ,    Στ = force*distance - 80 N.m = 0             F'*0.4 - 80 N.m = 0             F'*0.4 = 80          force F' = 200 N
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Romashka-Z-Leto [24]

Answer:

2 kg

Explanation:

Remember:

F = m * a       re-arrange to

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2 years ago
An electron in a vacuum is first accelerated by a voltage of 51400 V and then enters a region in which there is a uniform magnet
zimovet [89]

Answer:

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Explanation:

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Final. Electron with velocity, just out of the electric field

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Since the speed and the magnetic field are perpendicular the force that

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         Emo = U = q DV

Final. Electron with velocity, just out of the electric field

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          Emo = Emf

          .e DV = ½ m v2

          .v = RA 2 e DV / m

          .v = RA (2 1.6 10-19 51400 / 9.1 10-31)

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         F = q v x B

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5 0
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ikadub [295]

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8 0
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Answer:

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Explanation:

8 0
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