Question

Atividades de física 2°ano

Answer 1

1)

100 = L²

L =10cm

L = L₀ . (1 + α . ∆T) 

L = 10 . [1 + 2.10⁻³. (0 - 100)] 

L = 10 . (1 - 2.10⁻³ . 100) 

L = 10 . (1 - 0,2) 

L = 10 . 0,8 

L = 8

A = L²

A = 8²

A = 64 cm²

2)

∆L = a. L⁰ . ∆T

∆L = (1,2.10^-5) . (5) . (200-20)

∆L = (6.10^-5) . 1,8.10^2

∆L = 10,8.10^-3

∆L=1,08×10^-2 m

3)

C=Q/∆T

C=?

Q=1000cal

∆T=70-20=50°C

C=1000/50

C=20cal/°C

c=C/m

c=?

C=20cal/°C

m=500g

c=20/500

c=00,4cal/g.°C