A CD player rotates at a variable speed so that a laser can scan pits and lands on the disk’s bottom surface at a constant tange
1 answer:
Answer:
W = 0.384 J
Explanation:
Work and energy in the rotational movement are related
W = ΔK = - K₀
W = ½ I ² - 1 /2 I w₀²
where W isthe work, I is the moment of inertia and w angular velocity
With the system part of the rest the initial angular speed is zero (w₀ = 0)
The angular and linear quantities are related
v = w r
w = v / r
Let's replace
W = ½ I (v / r)²
Let's calculate
W = ½ 1.2 10⁻⁴ 1.2² / (1.5 10⁻²)²
W = 0.384 J
W = 38.4 J
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Complete Question:
In the same configuration of the previous problem 3, four long straight wires are perpendicular to the page, and their cross sections form a square of edge length a = 13.5 cm. Each wire carries 7.50 A, and the currents are out of the page in wires 1 and 4 and into the page in wires 2 and 3.
a) Draw a diagram in a (x,y) plane of the four wires with wire 4 perpendicular to the origin. Indicate the current's directions.
b) Draw a diagram of all magnetic fields produced at the position of wire 3 by the other three currents.
c) Draw a diagram of all magnetic forces produced at the position of wire 3 by the other three currents.
d) What are magnitude and direction of the net magnetic force per meter of wire length on wire 3?
Answer:
force, 1.318 ₓ 10⁻⁴
direction, 18.435°
Explanation:
The attached file gives a breakdown step by step solution to the questions
Answer:
Explanation:
Suppose v is the initial velocity and is the angle of inclination
distance traveled in vertical direction in t=1 s
When gravity is present
where
here initial velocity is v\sin \theta [/tex] so
In absence of gravity