Answer:
174.85 W
Explanation:
Area of plate = 3.14 x (15x 10⁻²)²
= 706.5 x 10⁻⁴ m²
heat being radiated by convection = 12 x 706.5 x 10⁻⁴ ( 180 - 15 )
= 139.88 W. This energy needs to be fed by heat source to maintain a constant temperature of 180 degree.
If power of electric source is P
P x .8 = 139.88
P = 139.88 / .8
= 174.85 W
Answer:
<em> It takes 186.67 second for the light to travel from Mars to earth.</em>
Explanation:
Light: Light is a visible form of energy which is radiated outward from a source. Light travels in a straight line, and this phenomenon is called rectilinear propagation of light.
S = d/t .......................... Equation 1
making t the subject of the equation
t = d/S ......................... Equation 2
Where S = speed of light, d = distance between the earth and Mars, t = time
<em>Given: d = 56000000 km, S = 300000 km per seconds.</em>
<em>Substituting these values into equation 2</em>
<em>t = 56000000/300000</em>
<em>t = 186.67 seconds.</em>
<em>Thus it takes 186.67 second for the light to travel from Mars to earth.</em>
Answer:
a) 
b) 
Explanation:
The energy of the photon (E) for
orbit of the hydrogen atom is given as:

where,
= 13.6 eV
n = orbit
a) Now for the transition from n = 4 to n = 5


b) Now for the transition from n = 5 to n = 6


Answer:
100-0 / 6 = 16.66 m/s
Explanation:
acceleration = vf-vi / time
vf= 100m/s
vi= 0 m/s
t= 6s