Answer:

Explanation:
Let the child is moving with speed same as the speed of water flow
So here the position of child with respect to flow must be zero
And if the boat start at an angle with the vertical
so its relative speed with flow of water is given as


now the time to reach the child is given as

so now we have

So the time to catch the child is given as


So distance moved by it in 0.104 h
distance moved by the boat in upstream direction given as


In y direction the displacement of boat is 

net displacement of the ball is given as



 
        
             
        
        
        
Answer:
Shawn's kinetic energy is 61.45 J.
Explanation:
Given;
Mass of the system is, 
Displacement of the bike is, 
Time taken is, 
Let the constant velocity be  .
.
For constant velocity, magnitude of velocity is given as distance by time.
Therefore, 
Now, kinetic energy of a body is given as:

Here, 

Therefore, Shawn's kinetic energy is 61.45 J.
 
        
             
        
        
        
The answer is D<span>.the gravitational force between the sun and each object in the solar system</span>
        
                    
             
        
        
        
Answer:
 true
Explanation:
 Friction occurs because no surface is perfectly smooth. Rougher surfaces have more friction between them. Heavier objects also have more friction because they press together with greater force. Friction produces heat because it causes the molecules on rubbing surfaces to move faster and have more energy.
 
        
                    
             
        
        
        
Answer:
B. 7.5 m/s^2
Explanation:
To find acceleration you need to subtract the final velocity by the starting velocity then divide that by the time
a= v-v/t
a= 60-0/8
a= 60/8
a=7.5 m/s^2