<span>Efficiency is the
measure of how efficient a process is. It is used to assess the ability of a
process in avoiding waste energy, materials, money and time in doing a
desirable output. It is calculated as;
Efficiency = useful energy ouput / total energy input</span>
<span>
.742 = useful energy / 200 J
Useful energy = 148.4 J <-----------OPTION B</span>
Use this formula to find your answer...
Determine the frequency of a clock waveform whose period is 2us or (micro) and 0.75ms
frequency (f)=1/( Time period).
Frequency of 2 us clock =1/2*10^-6 =10^6/2 =500000Hz =500 kHz.
Frequency of 0..75ms clock =1/0.75*10^-3 =10^3/0.75 =1333.33Hz =1.33kHz.
Answer:
C) 50 m/s
Explanation:
With the given information we can calculate the acceleration using the force and mass of the box.
Newton's 2nd Law: F = ma
- 5 N = 1 kg * a
- a = 5 m/s²
List out known variables:
- v₀ = 0 m/s
- a = 5 m/s²
- v = ?
- Δx = 250 m
Looking at the constant acceleration kinematic equations, we see that this one contains all four variables:
Substitute known values into the equation and solve for v.
- v² = (0)² + 2(5)(250)
- v² = 2500
- v = 50 m/s
The final velocity of the box is C) 50 m/s.
Complete Question
At what angle should the axes of two Polaroids be placed so as to reduce the intensity of the incident unpolarized light to 1/5.
Answer:
The angle is
Explanation:
From the question we are told that
The light emerging from second Polaroid is 1/5 the unpolarized
Generally the intensity of light emerging from the first Polaroid is mathematically represented as
Generally from the Malus law the intensity of light emerging from the second Polaroid is mathematically represented
=> 
=> 
From the question 
=> ![\theta = cos ^{-1} [\sqrt{\frac{2}{5}} ]](https://tex.z-dn.net/?f=%5Ctheta%20%3D%20%20%20cos%20%5E%7B-1%7D%20%5B%5Csqrt%7B%5Cfrac%7B2%7D%7B5%7D%7D%20%20%5D)
=> 
