The best thermal conductor is b. metal
Answer:
The size of the force developing inside the steel rod is 32039.28 N
Explanation:
Given;
length of the steel rod, L = 1.55 m
cross sectional area of the steel, A = 4.89 cm²
temperature change, ∆T = 28.0 K
coefficient of linear expansion for steel, α = 1.17 × 10⁻⁵ 1/K
Young modulus of steel, E = 200.0 GPa.
Extension of the steel is given as;
α ∆T L = FL / AE
α ∆T = F/AE
F = AEα ∆T
F = ( 4.89 x 10⁻⁴)(200 x 10⁹)(1.17 × 10⁻⁵)(28.0 K)
F = 32039.28 N
Therefore, the size of the force developing inside the steel rod when its temperature is raised, is 32039.28 N
Answer:
Astronomers use a method similar to the one you used with your homemade quadrant. Twice the distance to the Sun, divided by the distance to the star (which is unknown so far) is equal to the tangent of the parallax angle of the star.
Answer:
(c) 16 m/s²
Explanation:
The position is
.
The velocity is the first time-derivative of <em>r(t).</em>
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The acceleration is the first time-derivative of the velocity.

Since <em>a(t)</em> does not have the variable <em>t</em>, it is constant. Hence, at any time,

Its magnitude is 16 m/s².
Increase in speed or rate