Answer:
Two equal and opposite parallel forces not acting along the same line, form a couple. A couple is always needed to produce the rotation.
For example, turning a key in a lock and turning a steering wheel.
Answer:
(a) 
(b) P = 0.816 Watt
Explanation:
(a)
The power radiated from a black body is given by Stefan Boltzman Law:
where,
P = Energy Radiated per Second = ?
σ = stefan boltzman constant = 5.67 x 10⁻⁸ W/m².K⁴
T = Absolute Temperature
So the ratio of power at 250 K to the power at 2000 K is given as:
(b)
Now, for 90% radiator blackbody at 2000 K:
<u>P = 0.816 Watt</u>
Here's a quick way to find out. Pick up your glasses, bifocals work best, and find the focal length with a flashlight against a book. If I remember right, the object should be magnified and upside down. So, A.
Answer:
a) 6.9*10^14 Hz
b) 9*10^-12 T
Explanation:
From the question, we know that
435 nm is given as the wavelength of the wave, at the same time, we also know that the amplitude of the electric field, E(max) has been given to be 2.7*10^-3 V/m
a)
To find the frequency of the wave, we would be applying this formula
c = fλ, where c = speed of light
f = c/λ
f = 3*10^8 / 435*10^-9
f = 6.90*10^14 Hz
b) again, to find the amplitude of the magnetic field, we would use this relation
E(max) = B(max) * c, magnetic field amplitude, B(max) =
B(max) = E(max)/c
B(max) = 2.7*10^-3 / 3*10^8
B(max) = 9*10^-12 T
c) and lastly,
1T = 1 (V.s/m^2)
