Oh gosh oh I see it in my life face and
        
             
        
        
        
Answer:
u= 20.09 m/s
Explanation:
Given that
m = 0.02 kg
M= 2 kg
h= 0.2 m
Lets take initial speed of bullet = u m/s
The final speed of the system will be zero.
From energy conservation
1/2 m u²+ 0 = 0+ (m+M) g h
m u²=2 (m+M) g h
By putting the values
0.02 x u² = 2 (0.02+2) x 10 x 0.2       ( take g=10 m/s²)
u= 20.09 m/s
 
        
             
        
        
        
Answer:
Velocity of airplane is 500 km/h
Velocity of wind is 40 km/h
Explanation:
 = Velocity of airplane in still air
= Velocity of airplane in still air
 = Velocity of wind
= Velocity of wind
Time taken by plane to travel 1150 km against the wind is 2.5 hours

Time taken by plane to travel 450 km against the wind is 50 minutes = 50/60 hours

Subtracting the two equations we get

Applying the value of velocity of wind to the first equation

∴ Velocity of airplane in still air is 500 km/h and Velocity of wind is 40 km/h 
 
        
             
        
        
        
I think that in order for work to be done, the object must move in the direction of the force and move over a distance.