Complete question :
A 12 m x 15 m house is built on a 12-cm-thick concrete slab.
What is the heat-loss rate through the slab if the ground temperature is 5°C while the interior of the house is 25°C
Answer:
3kW
Explanation:
Given the following :
Dimension of house :
Length = 12m
Width = 15m
Thickness of concrete slab (t) = 12cm
t in metres :
100cm = 1m
12cm = (12/100)m
= 0.12m
Ground temperature (Tg) = 5°C
Interior temperature = (Th) = 25°C
Thermal conductivity of concrete (K) is approximately 1 Wm/k
Using the relation:
Q = KA * [ (Th - Tg) / d]
A = Length * width = (12 *15) = 180
Q = (1 * 180) * [(25°C - 5°C) / 0.12]
Q = 180 * (20/0.12)
Q = 180 * 16.6666
Q = 3,000W = 3kW
Answer:
Explanation:650
colour* wavelength (nm) energy (eV)
red 650 1.91
orange 600 2.06
yellow 580 2.14
green 550 2.25
-- She went up for 0.4 sec and down for 0.4 sec.
-- The vertical distance traveled in gravity during ' t ' seconds is
D = (1/2) x (g) x (t)²
= (1/2) (9.8 m/s²) (0.4 sec)²
= (4.9 m/s²) x (0.16 s²)
= 0.784 meter ( B )
Answer:
Explanation:
Radius = 9.5 x 10⁻² m
area of circle = 3.14 x (9.5 x 10⁻² )²
A = 283.38 x 10⁻⁴ m²
magnetic moment = area x current
M = 283.38 x 10⁻⁴ x 5
= 1416.9 x 10⁻⁴ Am²
Torque = MBsinθ
M is magnetic moment , B is magnetic field .
Max torque = 1416.9 x 10⁻⁴ x 3.4 x 10⁻³ , for θ = 90
= 4817.46 x 10⁻⁷
= 481.7 x 10⁻⁶
= 481.7 μ J
Energy = - MBcosθ
Max energy when θ = 180
MB = 4817.46 x 10⁻⁷ J
Min energy = - 4817.46 x 10⁻⁷ for θ = 0
It really all depends weather the temperature
