Answer:
Yes, Mirror are a surface that reflects light more perfectly than ordinary objects.
Explanation:
Atomic number=Proton count
Atomic mass=Proton count+ neutron count
Neuton Count=Atomic mass-Proton count
Proton count=Atomic number=27
Mass number=74
Neuton count= 74-27=47
Explanation:
It is given that,
Let Charge of
is taken from points A & B such that
.
We need to find the energy of charge. Electric potential is defined as the work done per unit of electric charge. So,

So, the energy of charge decreases by
. Hence, the correct option is (a).
Answer:
115799.256V/m
Explanation:
Given V = 623v, d = 5.38mm = 0.00538m
Strength of electric field E = V/d
E = 623/0.00538
= 115799.256V/m
Answer:
a= - 0.79 m/s²
Explanation:
Given that
Speed ,u = 20 mi/h
We know that
1 mi/h= 0.44 m/s
Therefore ,u = 8.94 m/s
Distance ,s= 50 m
Lets take the acceleration of the car = a m/s²
The final speed of the car ,v = 0 m/s
We know that
v²= u² + 2 a s
Now by putting the values
0²= 8.94² + 2 x a x 50

a= - 0.79 m/s²
Therefore the acceleration will be - 0.79 m/s².