Given:
distance from the projector lens to the image, di
projector lens focal length, f
distance from the transparency to the projector lens, do
thin lens equation: 1/f = 1/di + 1/do
do = 4 inches
di = 8 feet
convert feet to inches, for uniformity.
1 foot = 12 inches
8 feet * 12 inches/ft = 96 inches
1/f = 1/96 inches + 1/4 inches
Adding fractions, denominator must be the same.
1/f = (1/96 * 1/1) + (1/4 * 24/24)
1/f = 1/96 + 24/96
1/f = 25/96
to find the value of f, do cross multiplication
1*96 = f * 25
96 = 25f
96/25 = f
3.84 = f
The focal length of the project lens is 3.84 inches
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:
True
Explanation:
Cigarettes release over 5000 different chemicals when they burn and at least 70 of these can cause cancer.
Hope this helped!!!
Answer: option B: The resistor has a tolerance of 20%.
Explanation:
Resistors are color coded to identify their value and function. For a 3- Band resistor, reading from the left, first band denotes first digit, second band depicts second digit and third color depicts the multiplier. The absence of fourth band means the resistor has tolerance 20%.
Hence, the correct answer is option B. The resistor has a tolerance of 20%.
The answer is to the question is c
