Answer:
if im not mistaken i think its d let me know if correct plz
 
        
                    
             
        
        
        
Answer:
The resulting velocity of the ball after it hits the racket was of V= 51.6 m/s
Explanation:
m= 55.6 g = 0.0556 kg
t= 2.8 ms = 2.8 * 10⁻³ s
F= 1290 N/ms * t - 330 N/ms² * t²
F= 1024.8 N
F*t= m * V
V= F*t/m
V= 51.6 m/s
 
        
             
        
        
        
Answer:
168.57 mV 
Explanation:
Initial magnetic flux = BA , B magnetic field and A is area of loop
= .35 x 3.14 x .37²
= .15 Weber 
Final magnetic flux 
= - .2 x 3.14 x .37²
= -  .086 Weber
change in flux
.15 +  .086
= .236 Weber
rate of change of flux 
= .236 / 1.4 
= .16857 V 
= 168.57 mV 
 
        
             
        
        
        
K.E1=1/2×100×3²
 =50×9
 =450J
K.E2=1/2×100×36
 =50×36
 =1800J