Answer:
7.24 ohm
Explanation:
Let R1 and R2 are resistance of two resistors.
Emf=E=20 V
Current,I=2 A
Current,I'=10 A
We have to find the magnitude of the greater of the two resistances.
In series


By using the formula

...(1)
In parallel







Substitute the value




By using quadratic formula




Substitute the value


Hence, the magnitude of the greater of the two resistance=7.24 ohm
Answer:
The magnitude and direction of electric field midway between these two charges is
along AB.
Explanation:
Given that,
First charge 
second charge 
Distance = 20 cm
We need to calculate the electric field
For first charge,
Using formula of electric field

Put the valueinto the formula


Direction of electric field along AB
We need to calculate the electric field
For second charge,
Using formula of electric field

Put the valueinto the formula


Direction of electric field along AO
We need to calculate the net electric field at midpoint



Direction of net electric field along AB
Hence, The magnitude and direction of electric field midway between these two charges is
along AB.
This is problem of free falling
objects, which can be solved using the formula:
V = sqrt(2gy)
Where v is the velocity upon
impact
G is the acceleration due to
gravity ( 9.81 m/s2)
Y is the height
Since Venessa is 3.5 m
Y = 30 -3.5 = 26.5 m
V = sqrt(2 (9.81 m/s2) ( 26.5
m))
<span>V = 22.8 m/s</span>
Answer:
a. speed, v = 0.97 c
b. time, t' = 20.56 years
Given:
t' = 5 years
distance of the planet from the earth, d = 10 light years = 10 c
Solution:
(a) Distance travelled in a round trip, d' = 2d = 20 c = L'
Now, using Length contraction formula of relativity theory:
(1)
time taken = 5 years
We know that :
time = 
5 =
(2)
Dividing eqn (1) by v on both the sides and substituting eqn (2) in eqn (1):
Squaring both the sides and Solving above eqution, we get:
v = 0.97 c
(b) Time observed from Earth:
Using time dilation:


Solving the above eqn:
t'' = 20.56 years