Answer:
Work is measured as the product of force and the displacement in the direction of the force. Work = force × displacement in the direction of the force.
 
        
             
        
        
        
Answer:
a. 2 Hz b. 0.5 cycles c . 0 V
Explanation:
a. What is period of armature?
Since it takes the armature 30 seconds to complete 60 cycles, and frequency f = number of cycles/ time = 60 cycles/ 30 s = 2 cycles/ s = 2 Hz
b. How many cycles are completed in T/2 sec?
The period, T = 1/f = 1/2 Hz = 0.5 s.
So, it takes 0.5 s to complete 1 cycles. At t = T/2 = 0.5/2 = 0.25 s,
Since it takes 0.5 s to complete 1 cycle, then the number of cycles it completes in 0.25 s is 0.25/0.5 = 0.5 cycles.
c. What is the maximum emf produced when the armature completes 180° rotation? 
Since the emf E = E₀sinθ and when θ = 180°, sinθ = sin180° = 0
E = E₀ × 0 = 0
E = 0
So, at 180° rotation, the maximum emf produced is 0 V.
 
        
             
        
        
        
Given
Three 7 ohm resistor are in series.
The battery is V=10V
To find
The equivalent resistance
Explanation
When the resistance are in series then the resistance are added to find its equivalent.
Thus the equivalent resistance is:

Conclusion 
The equivalent resistance is 21 ohm
 
        
             
        
        
        
The weight changes but the mass will stay the same.
        
             
        
        
        
The answer is the red sidelight on a powerboat should be visible from the front and from the left (port side).
What are Sidelights?
- There is various combinations of lights that must be used on a boat when it is dark, and these are:
 - Sidelights: These lights are called combination lights and are red and green. The red sidelight must be visible from the port side and the green light indicates the right side (the starboard).
 - Stern light: The stern light is seen at the back end of the vessel.
 - Masthead Light: The masthead light is a white light that shines forwards and on all sides of the vessel. All powered vessels must use this light.
 - All-Round white light: This light is the major light that is used to join the masthead light and the stern light. This single light is visible to all vessels from all directions.
 - Thus, as a rule for a boat rider, he should show the vision of red light and it should be visible from the front and from the left (port side).
 
To learn more about Sidelights visit:
brainly.com/question/28205057
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