2.57 joule energy lose in the bounce
.
<u>Explanation</u>:
when ball is the height of 1.37 m from the ground  it has some gravitational potential energy with respect to hits the ground  
Formula for gravitational potential energy given by  
Potential Energy = mgh
Where
,
m = mass  
g = acceleration due to gravity  
h = height
Potential energy when ball hits the ground
m= 0.375 kg
h = 1.37 m
g = 9.8 m/s²

Potential Energy = 5.03 joule
Potential energy when ball bounces up again
h= 0.67 m

Potential Energy = 2.46 joule
Energy loss = 5.03 - 2.46 = 2.57 joule
2.57 joule energy lose in the bounce
 
        
             
        
        
        
Answer:
1.785 m/s
Explanation:
The momentum can be calculated using the expression below
M1 *V1 + M2 * V2 = (M1+M2) V3
M1= mass of van=9000 kg
M2= mass of car= 850kg
V3= velocity of entangled car
V1= Velocity of the van= 0 
V2= velocity of the car= 5 m/ s
Substitute the values
(900×0) + (500×5)=( 900+500)× V3
2500=1400 V3
V3=2500/1400
V3= 1.785 m/s
Hence, velocity of the entangled cars after collision is 1.785 m/s
 
        
             
        
        
        
Answer:
7.08 m/s²
Explanation:
Given:
v₀ = 20.0 m/s
v = 105 m/s
t = 12.0 s
Find: a
v = at + v₀
105 m/s = a (12.0 s) + 20.0 m/s
a = 7.08 m/s²
 
        
             
        
        
        
Not at all. Density on its own is not sufficient