Answer:
9.6 Ns
Explanation:
Note: From newton's second law of motion,
Impulse = change in momentum
I = m(v-u).................. Equation 1
Where I = impulse, m = mass of the ball, v = final velocity, u = initial velocity.
Given: m = 2.4 kg, v = 2.5 m/s, u = -1.5 m/s (rebounds)
Substitute into equation 1
I = 2.4[2.5-(-1.5)]
I = 2.4(2.5+1.5)
I = 2.4(4)
I = 9.6 Ns
 
        
             
        
        
        
Answer:
3 hours
Explanation:
180 divided by 60 (mph means miles per hours by the way)
 
        
             
        
        
        
Explanation:
A micrometer, sometimes known as a micrometer screw gauge, is a device incorporating a calibrated screw widely used for accurate measurement of components in mechanical engineering and machining as well as most mechanical trades, along with other metrological instruments such as dial, vernier, and digital calipers
  
        
             
        
        
        
Answer: 0.16Hz
Explanation:
Given that:
wavelength (λ) = 125 meters
speed (V) = 20 m/s
frequency (F) = ?
Recall that frequency is the number of cycles the wave complete in one second. And its value depends on the wavelength and speed of the wave.
So, apply the formula V = F λ
Make F the subject formula 
F = V / λ
F = 20 m/s / 125 meters
F = 0.16 Hz
Thus, the frequency of the wave is 0.16 Hertz.