Answer:
(A) -2940 J
(B) 392 J 
(C) 212.33 N
Explanation:
mass of bear (m) = 25 kg
height of the pole (h) = 12 m
speed (v) = 5.6 m/s
acceleration due to gravity (g) = 9.8 m/s
(A) change in gravitational potential energy (ΔU) = mg(height at the bottom- height at the top)
height at the bottom = 0
          = 25 x 9.8 x (0-12) = -2940 J
(B) kinetic energy of the Bear (KE) =  
 
            =  = 392 J
  = 392 J 
(C) average frictional force = 
- change in KE (ΔKE) = initial KE - final KE 
- ΔKE =  - -  
- when the Bear reaches the bottom of the pole, the final velocity (Vf) is 0, therefore the change in kinetic energy becomes  ΔKE =  - 0 = 392 J - 0 = 392 J
  \frac{-(ΔKE+ΔU)}{h}[/tex] =  
 
 =   = 212.33 N
 = 212.33 N
 
        
             
        
        
        
Answer:a substance with low ability or no ability to conduct energy 
Explanation:
 
        
             
        
        
        
Answer:
Skeletal system, muscular system
Explanation:
Skeletal system:
bones
Muscular system:
muscles
Together, they work together and create the musculoskeletal system.
 
        
                    
             
        
        
        
Answer:
12.5 m/s
Explanation:
From the question given above, the following data were obtained:
Initial velocity (u) = 0 m/s 
Height (h) = 8 m
Final velocity (v) at 8 m above the lowest point =?
NOTE: Acceleration due to gravity (g) = 9.8 m/s²
The velocity of the roller coaster at 8 m above the lowest point can be obtained as follow:
v² = u² + 2gh
v² = 0² + (2 × 9.8 × 8)
v² = 0 + 156.8
v² = 156.8
Take the square root of both side 
v = √156.8
v = 12.5 m/s
Therefore, the velocity of the roller coaster at 8 m above the lowest point is 12.5 m/s.