Answer:
distance between the dime and the mirror, u = 0.30 m
Given:
Radius of curvature, r = 0.40 m
magnification, m = - 2 (since,inverted image)
Solution:
Focal length is half the radius of curvature, f = 
f = 
Now,
m = - 
- 2 = -
= 2 (2)
Now, by lens maker formula:
v = 
(3)
From eqn (2):
v = 2u
put v = 2u in eqn (3):
2u =
2 = 
2(u - 0.20) = 0.20
u = 0.30 m
Answer: The average velocity is 150 km/h
Explanation: 70+80=150
Im pretty sure that they do
Answer:
B = 0.129 T
Explanation:
Given,
frequency, f = 60 Hz
maximum emf = 5200 V
Number of turns, N = 130
Area per turn = 0.82 m²
We know,
ω = 2 π f
ω = 2 π x 60 = 376.99 rad/s
now, Magnetic field calculation
B = 0.129 T
Hence, the magnetic field is equal to B = 0.129 T
Answer:
R1 = 5.13 Ω
Explanation:
From Ohm's law,
V = IR............... Equation 1
Where V = Voltage, I = current, R = resistance.
From the question,
I = 2 A, R = R1
Substitute into equation 1
V = 2R1................ Equation 2
When a resistance of 2.2Ω is added in series with R1,
assuming the voltage source remain constant
R = 2.2+R1, and I = 1.4 A
V = 1.4(2.2+R1)................. Equation 3
Substitute the value of V into equation 3
2R1 = 1.4(2.2+R1)
2R1 = 3.08+1.4R1
2R1-1.4R1 = 3.08
0.6R1 = 3.08
R1 = 3.08/0.6
R1 = 5.13 Ω
