Answer:
Explanation:
Commonly area is a scalar quantity because there is no need of direction to define and also follow the algebrac summation. When we talk about vector there exist a frame of reference with a certain orogin
Answer:
- Gap between the plates
- No, practically not achievable
Solution:
As per the question:
Capacitance, C = 1 F
Area of the plate of the capacitor, A =
Now,
To calculate the distance, D between the plates of a parallel plate capacitor:
Thus
where
= permittivity of free space
Now,
This distance much smaller and is practically not possible
Answer:
The average distance is 999.936 light years.
Solution:
As per the question:
Ours is the Milky Way Galaxy with the diameter:
D = 1,00,000 ly
Radius, R =
Now,
A =
The area to each civilization, A' is:
A' =
The radius of each area of civilization, r:
Thus the average separation distance between civilizations is given as:
2r =
The change in frequency is called the Doppler effect. The speed of the car can be calculated by the formula for the Doppler effect for when the observer is standing still and the source of the sound is moving towards him:
f¹={V/(V-Vs)}*f,
where f¹ is the frequency of the car while moving towards the observer, V=343 m/s is the speed of sound, Vs is the speed of the car and f is the frequency of the car while standing still.
We need to solve the equation for the Vs:
f¹/f=V/(V-Vs)
V-Vs=V/(f/f¹)
-Vs=V/(f/f¹)-V
Vs=-V/(f/f¹)+V= -343/(300/330)+343=-343*0.91+343=-312.1+343=30.9 m/s
So the speed of the moving police car is Vs=30.9 m/s.
Answer:
a. 960 W b. One 1 kW room heater
Explanation:
a. The rate of heat conduction P = kA(T₂ - T₁)/d where k = 2 × 0.040 W/m-K = 0.080 W/m-K since the thermal conductivity of glass wool is 0.040 W/m-K and that of the material is twice the thermal conductivity of glass wool, A = area of walls = 120 m², T₁ = outside surface temperature = 5.0 °C, T₂ = inside surface temperature = 18.0 °C and d = thickness of wall = 13.0 cm = 0.13 m
P = kA(T₂ - T₁)/d
= 0.080 W/m-K × 120 m²(18.0 °C - 5.0 °C)/0.13 m
= 9.6 Wm/K × 13 K/0.13 m
= 124.8 Wm/0.13 m
= 960 W
b. The number of 1 kW room heater required will be
n = rate of heat conduction/power of one room heater = 960 W/ 1 kW = 960 W/1000 W = 0.96 ≅ 1
So we need only one 1 kW room heater.