Answer:
The average power is calculated as 735.0 W
Solution:
As per the question:
Total mass, M = 1200 kg
Counter mass of the elevator, m = 950
Distance traveled by the elevator, d = 54 m
Time taken, t = 3 min = 180 s
Now,
To calculate the average power:
First, we find the force needed for lifting the weight:
Force, F = (M - m)g = 
Now, the work done by this force:
W = Fd = 
Average power is given as:

Answer: its a strip of transparent film, one side coated with gelatin emulsion containing microscopically small light-sensitive silver halide crystals
Explanation:
Kinetic energy because of the wood plank is just still and not moving it’s potential but since it’s asking which one it doesn’t have it doesn’t have kinetic energy cause it’s not moving
Answer:
d = 1.55 * 10⁻⁶ m
Explanation:
To calculate the distance between the adjacent grooves of the CD, use the formula,
..........(1)
The fringe number, m = 1 since it is a first order maximum
The wavelength of the green laser pointer,
= 532 nm = 532 * 10⁻⁹ m
Distance between the central maximum and the first order maximum = 1.1 m
Distance between the screen and the CD = 3 m
= Angle between the incident light and the diffracted light
From the setup shown in the attachment, it is a right angled triangle in which


Putting all appropriate values into equation (1)

The answer is B. Unbalanced force