The active element of a certain laser is made of a glass rod 31.0 cm long and 1.30 cm in diameter. assume the average coefficient of linear expansion of the glass is equal to 9.00 10-6 (°c)-1. the temperature of the rod increases by 62.0°c.
what is the increase in its length?
(a) what is the increase in its length?
(b) what is the increase in its diameter?
(c) what is the increase in its volume?

(a) ΔL=0.172 mm

(b) Δd=7.254×10⁻³mm

(c) ΔV=21.92 mm

Explanation:

Given data

L(length)=31.0cm→310mm

d (diameter)=1.30cm→13 mm

α(Coefficient)=9.00×10⁻⁶ °C⁻¹

T (Temperature)=62 °C

(a) ΔL=?

(b) Δd=?

(c) ΔV=?

Solution

For (a) ΔL part

ΔL=α×LΔT

ΔL=(9.00×10⁻⁶)×(310)×(62)

ΔL=0.172 mm

For  (b) Δd part

Area is π×r² but diameter is just 2π×r

Δd=α×dΔT

Δd=(9.00×10⁻⁶)×(13)×(62)

Δd=7.254×10⁻³mm

For (c) ΔV part

Volume is Lπ×r² and α is 3α

ΔV=3α (Lπ×r²)×62

ΔV=3×(9.00×10⁻⁶)×(310×(13/2)²) ×62

ΔV=21.92 mm

c. rb

explanation:

the atomic radius of a chemical element is a measure of the size of its atoms, usually the mean or typical distance from the center of the nucleus to the boundary of the surrounding shells of electrons.

when a device is used in a circuit in which the voltage is 81 v, the current flowing through the device is 3 a. what is the resistance of the device?

a. 27 ω

b. 40.5 a

c. 243 ω

d. 243 a

the correct answer is a. 27