The net force acting on the car is 3 which slows the car down.
        
             
        
        
        
Answer:
Time period is directly proportional to the length so if the length is doubled the time period is doubled
hope it is helpful....
 
        
                    
             
        
        
        
I just figured this out now.
First you would use the formula
Ephoton= hc/λ and substitute in the value's of plank's constant, the speed of light in a vaccum and the wavelength which will give you the energy in joules. Then you go to the reference table and solve for the energy used between the different levels for Mercury making sure to convert electron volts to jules. In the end the correct answer should be energy level D.
        
             
        
        
        
Answer:
Explanation:
Image of distant object will be made at far point or at 52.5 so 
object distance u = infinity
image distance v = - 52.5 cm
focal length required = f 
Lens formula 
1 / v - 1 / u = 1 / f 
1 /  - 52.5 - 0 = 1 / f 
f =  -52.5 cm 
= -.525 m 
Power P = 1 / f = -  1 / .525
= -  1.90 
now , for eye with glass we shall find new near point . 
v = ?
u = - 17.2 cm 
f = -  52.5 cm 
1 / v - 1 / u = 1 / f 
   1 / v + 1 / 17.2 = -  1 / 52.5 
1 / v  = - 1 / 17.2 -    1 / 52.5 
= - .05813 -  .019
= - .07713
u = - 12.96 cm 
so new near point will be 12.96 cm