C.
Explanation: Because mirrors are lighter, and they are easier than lenses to make perfectly smooth.
First box and third box !
Answer:
130.22 g
Explanation:
Parameters given:
Mass of water Mw = 225 g
Mass of stirrer Ms = 40 g
Mass of silver M(S) = 410 g
By applying the law of conservation of energy:
(McCc + MsCs + MwCw)ΔTw = M(S)C(S)ΔT(S)
where Mc = Mass of cup
Cc = Specific heat capacity of aluminium cup = 900 J/gC
Cs = Specific heat capacity of copper stirrer = 387 J/gC
Cw = Specific heat capacity of water = 4186 J/gC
ΔTw = change in temperature of water = 32 - 27 = 5 °C
C(S) = Specific heat capacity of silver = 234 J/gC
ΔT(S) = change in temperature of silver = 88 - 32 = 56 °C
Therefore:
[(Mc * 900) + (40 * 387) + (225 * 4186)] * 5 = 410 * 234 * 56
(900Mc + 957330) * 5 = 5276700
900Mc + 957330 = 5276700 / 5 = 1074528
900Mc = 1074528 - 957330
900Mc = 117198
Mc = 117198/ 900
Mc = 130.22 g
The mass of the cup is 130.22 g.
Answer:
l= 3.002 cm
Explanation:
Given that
n= 70 turns
B= 1.2 T
θ= 15°
I= 1.5 A
τ = 0.0294 N⋅m
Lets take length of sides is l.
We know that
τ = n I A B sin θ
Area of square ,A= l²
Now by putting the value
τ = n I A B sin θ
0.0294 = 70 x 1.5 x l² x 1.2 x sin 15°
l² = 0.000901 m²
l² = 9.01 cm²
l= 3.002 cm
