Answer:
correct option is d) 7.0 x 10^-7 N
Explanation:
given data
distance = 175 picometers = 1.75 ×
m
to find out
electrical force
solution
we know atomic no of uranium is 92
and charge on electron is = 1.6 ×
C
and electrical force is express as
electrical force =
.............1
put here value we get
electrical force = 
electrical force = 6.921 ×
N
so correct option is d) 7.0 x 10^-7 N
Answer:
Vmax=11.53 m/s
Explanation:
from conservation of energy

Spring potential energy =potential energy due to elevation
0.5*k*x²= mg
=mgh
0.5*k*2.3²= 430*9.81*6
k=9568.92 N/m
For safety reason
k"=1.13 *k= 1.13*9568.92
k"=10812.88 N/m
agsin from conservation of energy

spring potential energy=change in kinetic energy
0.5*k"*x²=0.5*m*
10812.88 *2.3²=430*
=11.53 m/s
Complete Question
A certain refrigerator, operating between temperatures of -8.00°C and +23.2°C, can be approximated as a Carnot refrigerator.
What is the refrigerator's coefficient of performance? COP
(b) What If? What would be the coefficient of performance if the refrigerator (operating between the same temperatures) was instead used as a heat pump? COP
Answer:
a

b
Explanation:
From the question we are told that
The lower operation temperature of refrigerator is
The upper operation temperature of the refrigerator is 
Generally the refrigerators coefficient of performance is mathematically represented as

=> 
=> 
Generally if a refrigerator (operating between the same temperatures) was instead used as a heat pump , the coefficient of performance is mathematically represented as
=>
=>
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