Answer:
8.333*10^-6 ohms
Explanation:
Resistivity of a material is expressed as;
p = RA/l
R is the resistance of the material
A is the cross sectional area
l is the length of the material
Given
R = 5 ohms
A = 0.5mm^2
A = 5 * 10^-7m^2
l = 30cm = 0.3m
Substitute into the formula;
p = (5 * 5 * 10^-7m^2)/0.3
p = 25 * 10^-7/0.3
p = 0.0000025/0.3
p = 8.333*10^-6
Hence its resistivity at 20 degrees Celsius is 8.333*10^-6 ohms
Answer:
55.8W
Explanation:
P= V^2/R
R= V^2/P
For series connection
Req= R1+ R2= V^2/310 + V^2/180
R=V^2/P= V^2/310 + V^2/180
But V^2 will cancel out
P= 1/(1/310 + 1/180)
P= 55.8W
Answer:
F=1.4384×10⁻¹⁹N
Explanation:
Given Data
Charge q= -8.00×10⁻¹⁷C
Distance r=2.00 cm=0.02 m
To find
Electrostatic force
Solution
The electrostatic force between between them can be calculated from Coulombs law as

Substitute the given values we get

Answer:
v = 1 m/s
Explanation:
from the principle of conservation of momentum, we have following relation
initial momentum = final momentum

where
m1 = 1.14 kg
v1 = 2.0 m/s
m2 = 1.14 kg
v2 = 0 m/s
putting all value in the above equation


v = 1 m/s
Answer:

Explanation:
Let the length of the string is L.
Let T be the tension in the string.
Resolve the components of T.
As the charge q is in equilibrium.
T Sinθ = Fe ..... (1)
T Cosθ = mg .......(2)
Divide equation (1) by equation (2), we get
tan θ = Fe / mg




As θ is very small, so tanθ and Sinθ is equal to θ.

