Answer:
Option (2) is correct.
The energy density of an electromagnetic wave is equally divided between the magnetic and electric fields.
Explanation:
An electromagnetic waves are the waves which are produced when the oscillating electric and magnetic field are interact each other perpendicular to each other. The direction of propagation of electro magnetic waves is perpendicular to each electric and magnetic fields.
The energy associated with the electromagnetic waves is equally distributed in form of electric and magnetic fields.
So, the correct option is (2).
I am like 98% sure it is C
Ir=Initial Intensity/Area of spread=Io4πr2
Ir∝1r2
It is seen from this expression that intensity is inversely proportional to the square of the distance. As we move away from the light source the intensity decreases at the rate of square of the distance from the source.
Brightness being the perception of intensity. more the intensity more bright the object is perceived and vice versa.
Answer:
The net displacement of the car is 3 km West
Explanation:
Please see the attached drawing to understand the car's trajectory: First in the East direction for 4 km (indicated by the green arrow that starts at the origin (zero), and stops at position 4 on the right (East).
Then from that position, it moves back towards the West going over its initial path, it goes through the origin and continues for 3 more km completing a moving to the West a total of 7 km. This is indicated in the drawing with an orange trace that end in position 3 to the left (West) of zero.
So, its NET displacement considered from the point of departure (origin at zero) to the final point where the trip ended, is 3 km to the west.
Work = (force) x (distance)
(550 newtons) x (0.5 meter) = 275 joules each lift .
(275 joules/lift) x (10 lifts) = 2,750 joules of work all together.
Power = (work done) / (time to do the work)
= (2,750 joules) / (20 seconds)
= 137.5 watts . (about 0.18 horsepower)