Answer:
n = 10 beats 
Explanation:
Given:
- Frequency of note f1 = 151 Hz
- Frequency of note f2 = 155 Hz
- The total time they ring t = 2.5 s
Find:
How many beats are heard
Solution:
- The frequency of beat (fb) is the difference between the two frequencies of notes as follows:
                                 fb = f2 - f1
                                 fb = 155 - 151
                                 fb = 4 Hz
- The number of beats per second is also called beat frequency:
                                 n = fb*t
                                 n = 4*2.5
                                 n = 10 beats 
            
 
        
             
        
        
        
Answer: the last period. i think has the largest energy level
Explanation:
 
        
                    
             
        
        
        
<span>
be aware of large trucks on the roadway
Tip: usually, these signs are hazard signs or warning.
Also, this isnt physics </span><span />
        
                    
             
        
        
        
Answer:
h = 2.5 m
Explanation:
Given that,
Mass of a ball, m = 1.5 kg
Initial velocity of the ball, u = 7 m/s
We need to find the maximum height reached by the ball. Let it is be h. Using the conservation of energy to find it such that,

Put all the values,

So, it will reach to a height of 2.5 m.