I believe the answer is #4. u can always ask google if u believe that's the wrong answer :)
Answer:
47.76°
Explanation:
Magnitude of dipole moment = 0.0243J/T
Magnetic Field = 57.5mT
kinetic energy = 0.458mJ
∇U = -∇K
Uf - Ui = -0.458mJ
Ui - Uf = 0.458mJ
(-μBcosθi) - (-μBcosθf) = 0.458mJ
rearranging the equation,
(μBcosθf) - (μBcosθi) = 0.458mJ
μB * (cosθf - cosθi) = 0.458mJ
θf is at 0° because the dipole moment is aligned with the magnetic field.
μB * (cos 0 - cos θi) = 0.458mJ
but cos 0 = 1
(0.0243 * 0.0575) (1 - cos θi) = 0.458*10⁻³
1 - cos θi = 0.458*10⁻³ / 1.397*10⁻³
1 - cos θi = 0.3278
collect like terms
cosθi = 0.6722
θ = cos⁻ 0.6722
θ = 47.76°
This question is incomplete, the complete question is;
A weightlifter holds a 1,300 N barbell 1 meter above the ground. One end of a 2-meter-long chain hangs from the center of the barbell. The chain has a total weight of 400 N. How much work (in J) is required to lift the barbell to a height of 2 m?
What is the average force (average with respect to height of the barbell from the ground) exerted by the weightlifter in the process?
Answer: Average force exerted by the weightlifter in the process = 1600N
Explanation:
To find Work done to lift a barbell and half of the hanging chain we say;
W₁ = ( 1300N + (1/2 × 400N)) × 1m
W₁ = (1300 + 200) Nm
W₁ = 1500J
now work done to lift the upper half of the chain we say:
W₂ = (1/2 × 400N) × (1/2 × 1m)
W₂ = 200N × 0.5m
W₂ = 100J
So total work done will be
W = W₁ + W₂
W = 1500J + 100J
W = 1600J
To find the average force exerted by the weight lifter, we say;
F = W/D
F = (1600 / 1m) N
F = 1600N
∴Average force = 1600N
D = V0t + 0.5at^2
Where d is the distance
V0 is the initial velocity
A is the acceleration
T is time
From the graph a = 4/3 m/s2
D = 0(3) + 0.5( 4/3 m/s2) ( 3 s)^2
D = 6 m
Answer:
similar wave amplitudes
Explanation:
When two waves travelling in the same medium have similar wave amplitudes they are less likely to interfere with each other destructively or constructively because the interference between waves occur when the amplitudes of the waves arrive a position in the medium in opposite directions hence they add up( superposition) or cancel each other out.
Hence if the waves have similar wave amplitudes the interference between the waves will be limited.
