1).  The little projectile is affected by friction all the way through the block.
Friction robs some kinetic energy.
2).  The block is affected by friction as it scrapes along the top of the post.
Friction robs some kinetic energy.
3).  The block is also affected by friction with the air (air resistance) as it
falls to the ground.  Friction robs some kinetic energy.
        
             
        
        
        
Heat absorbed by the solar collector = Area*Irradiance = 5.3*995 = 5273.5 W
Heat Q in joules absorbed in t hours = Heat used to heat water. That is,
5273.5*t = mCΔT; where mass = volume*density = 1*1000 = 1000 kg
Therefore;
5273.5t = 1000*4186*(65-20) = 188370000
t = 188370000/5273.5 = 35720.11 seconds = 35720.11/(60*60) hours ≈ 9.92 hours.
It will take approximately 9.92 hours.
        
             
        
        
        
Answer:
2.64N  
Explanation:
Force = mass * acceleration
Given
mass = 4kg
distance = 1.9m
Time t = 2.4s
Get the acceleration using the equation of motion
S = ut + 1/2at²
1.9 = 0 + 1/2a(2.4)²
1.9 = 5.76a/2
1.9 = 2.88a
a = 1.9/2.88
a = 0.66m/s²
Get the magnitude of the force
Force = 4 * 0.66
Force = 2.64N
Hence the net force acting on the fish is 2.64N  
 
        
             
        
        
        
Answer:
The acceleration of the wagon is 3 m/s².
To calculate the acceleration of the wagon, we use the formula below.
Formula:
F = ma............. Equation 1
Where:
F = horizontal Force
m = mass of the wagon
a = acceleration of the wagon.
make a the subject of the equation
a = F/m.............. Equation 2
From the question,
Given:
F = 30 N
m = 10 kg
Substitute these values into equation 2
a = 30/10
a = 3 m/s²
Hence, the acceleration of the wagon is 3 m/s².