<span>If the maximum permissible limit for depression of the structure is 20 centimeters, the number of floors that can be safely added to the building is </span><span>C. 18</span>
depression = (depression/floor)(# floors) < 20
Here are the following choices:
<span>A.
14
B.
15
C.
18
D.
23</span>
Answer:
2.5 m
Explanation:
Weight of billboard worker = 800 N
Number of ropes = 2
Length of scaffold = 4 m
Weight of scaffold = 500 N
Tension in rope = 550 N
The sum of the torques will be

The position of the person will be 2.5 m
A photoelectric cell is an electronic device which is used to convert light energy into electric energy.The operation of this device is based on photoelectric effect.
Light of suitable frequency i.e greater or equal to threshold frequency will fall on the cathode maintained at negative potential.The electron emission will take place and these electrons are drifted towards the anode which is at positive potential.
Here,only those radiations will be capable of emitting electrons irrespective of surface barrier of metals whose energy is greater than the work function.
We know that the radiation having long wavelength has least energy as energy and wavelength are inversely proportional to each other.

Here h is the Planck's constant,c is the velocity of light.
Here we have been given red light and blue light.
In the visible spectrum of radiation, the red light has longer wavelength than all other colors of light.Hence blue light has more energy as it's wavelength is less as compared to red light.
Hence, the blue light will activate the most and red the least.
Answer:
Explanation:
A) When a dipole is placed in an electric field , it experiences a torque equal to the following
torque = p x E = p E sinθ , where θ is angle between direction of p and E .
It will be zero if θ = 0
or if both p and E are oriented in the same direction.
It is the stable orientation of dipole.
If θ = 180° ,
Torque = 0
In this case both p and E are oriented in opposite direction .
It is the unstable orientation of the dipole because if we deflect the dipole by even small angle , it goes back to most stable orientation due to torque acting on it by electric field.
Answer:
<h2>
The potential difference increases </h2>
Explanation:
from the relation 
where E= electric field (force per coulomb)
V= voltage
d= distance
Hence the voltage is going to be V= E×d.
Therefore this means that increasing the distance increases the voltage.