Answer:
b). False
Explanation:
A refractory material is a type of material that can withstand high temperatures without loosing its strength. They are used in reactors, furnaces, kilns, etc.
Refractory materials are certain super alloys and ceramics materials.
Properties of refractory materials :
1. Refractory materials have high melting point.
2.They acts barriers between high heat zone and low heat zone.
3. The specific heat of refractory material is very low.
4. Refractories that have high bulk densities are better in quality.
Hence, Refractory materials have a very high melting temperature.
Answer:
the maximum thermal efficiency is 29%
Explanation:
the maximum efficiency for a thermal engine that works between a cold source and a hot source is the one of a Carnot engine. Its efficiency is given by
Maximum efficiency= 1 - T2/T1
where
T2= absolute temperature of the cold sink (environment)= 20°C + 273 = 293
T2= absolute temperature of the hot source (hot water supply) = 140°C + 273 = 413
therefore
Maximum efficiency= 1 - T2/T1 = 1 - 293/413 = 0,29 =29%
Answer:
The final temperature of water is 381.39 °C.
Explanation:
Given that
Mass of water = 5 kg
Heat transfer at constant pressure Q = 2960 KJ
Initial temperature = 240 °C
We know that heat transfer at constant pressure given as follows

We know that for water

Lets take final temperature of water is T
So


T=381.39 °C
So the final temperature of water is 381.39 °C.
Answer:
See explanation
Explanation:
The magnetic force is
F = qvB sin θ
We see that sin θ = 1, since the angle between the velocity and the direction of the field is 90º. Entering the other given quantities yields
F
=
(
20
×
10
−
9
C
)
(
10
m/s
)
(
5
×
10
−
5
T
)
=
1
×
10
−
11
(
C
⋅
m/s
)
(
N
C
⋅
m/s
)
=
1
×
10
−
11
N