The intensity on a screen 20 ft from the light will be 0.125-foot candles.
<h3>What is the distance?</h3>
Distance is a numerical representation of the length between two objects or locations.
The intensity I of light varies inversely as the square of the distance D from the source;
I∝(1/D²)
The ratio of the intensity of the two cases;

Hence, the intensity on a screen 20 ft from the light will be 0.125 foot-candles
To learn more about the distance refer to the link;
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(a) The average speed from A to B would be 1.76 metre per second and the average velocity from A to B would also be 1.76 metre per second
<span>(b) The average speed from A to C would be 1.73 metre per second and the average velocity from A to C would be 0.87 metre per second</span>
Explanation:
We have,
Mass of an object is 0.5 kg
Force constant of the spring is 157 N/m
The object is released from rest when the spring is compressed 0.19 m.
(A) The force acting on the object is given by :
F = kx

(B) The force is simply given by :
F = ma
a is acceleration at that instant

Answer: The option (C) is correct. The energy travels horizontally.
Explanation: When the pebble is thrown into a calm lake, there will be disturbance in the lake. The ripples are formed from the center and move outward because the energy is carried out from particle to particle.
The distribution of the energy among the particles starts from center and it will carry out outward. This disturbance will occur horizontally.
Therefore, the energy travels horizontally.