Answer:
The magnitude of the average frictional force on the block is 2 N. 
Explanation:
Given that.
Mass of the block, m = 2 kg
Initial velocity of the block, u = 10 m/s
Distance, d = 50 m
Finally, it stops, v = 0
Let a is the acceleration of the block. It can be calculated using third equation of motion. It can be given by :



The frictional force on the block is given by the formula as :
F = ma

|F| = 2 N
So, the magnitude of the average frictional force on the block is 2 N. Hence, this is the required solution.
 
        
             
        
        
        
Answer:
a = 0 m/s²
Explanation:
given,
car moving at steady velocity = 100 Km/h
          1 km/h = 0.278 m/s
       100 Km/h = 27.8 m/s
time of acceleration = 100 s
acceleration is equal to change in velocity per unit time.
  
change in velocity of the car is 27.8 - 27.8 = 0
  
         a = 0 m/s²
If the car is moving with steady velocity then acceleration of the car is zero.
Hence, the acceleration of the car is equal to a = 0 m/s²
 
        
             
        
        
        
You need an additional point of data here: the enthalpy of fusion, or conversely the enthalpy of melting (they differ only by their sign). For water (or ice) that value is gotten from sources such as the internet
<span>ΔH°(fus) = 6.01 kJ/mole </span>
<span>Since you have 35 000g, how many moles do you have? </span>
<span>Moles H2O = 35000 g/(18.015 g/mole) = 1942.8 moles</span>
<span>So, take that ΔH°(fus) in kJ/mole, multiply by the number of moles, and there ya go! 
</span>
6.01 x 1942.8 = 11,676 kJ of energy is released
Hope I helped!! xx
        
             
        
        
        
In calculating the energy of a photon of light, we need the relationship for energy and the frequency which is expressed as:
 
E=hv 
where h is the Planck's constant (6.626 x 10-34 J s)and v is the frequency.
E = 6.626 x 10-34 J s (<span>7.33 x 10^14 /s) = 4.857 x 10^-19 J</span>
        
             
        
        
        
Answer:
The Gravitational Force is reduced 4 times
Explanation:
The equation of Gravitational force follows:
F = (G*m1*m2)/r^2
Assume that G*m1*m2 = 1 and r = 1:
F = 1/1^2 = 1 N
Multiply the radius by 2
F = 1/2^2 = 1/4 N
So doubling the distance reduces the force 4 times.