Answer:
3) C
4 D
5) C
Explanation:
3) given that
Initial distance of the screen = 100cm
Initial area = 150 cm^2
Final distance = 200 cm
The intensity of light is inversely proportional to the square of the distance. That is
Intensity of light I = 1/d2
And also I = P/A
1/d^2 = P/A
P = A/d^2
P1 = P2
150/100 = A/200
1.5 = A/200
A = 1.5 × 200
A = 300 cm^2
4.) Light is projected onto a screen 75.0 cm from a light source. The light intensity = 4436 lux
If the screen is moved from 75.0 cm to 150. cm, the light sensor reading will be
Using inverse square law
I = 1/d^2
I×d^2 = constant. Therefore,
4436 × 75^2 = I × 150^2
I = 24952500/22500
I = 1109 lux
5.) We can express the relationship between luminosity, brightness, and distance with a simple formula.
As we tilt the serene the area of light decreases and makes the light more concentrated.
Answer:
he same direction the magnitude of the resultant is equal to the scalar sum of the magnitude of the forces, but if they are applied in different directions the magnitude must be found using the Pythagorean theorem
Explanation:
When there are several applied forces, if they are all in the same direction the magnitude of the resultant is equal to the scalar sum of the magnitude of the forces, but if they are applied in different directions the magnitude must be found using the Pythagorean theorem, so which the resulting dowry is less than the sum of the magnitudes.
Let's carry out an example with two forces, F1 and F2 of equal magnitudes
if they are in the same direction
F_total = F₁ + F₂ = 2 F
if they are at 90º
F_total = 
if they are at 180º
F_total = F₁ -F₂ = 0
True.........................................
<h2>
Answer:</h2>
0.31425 Tesla
<h2>
Explanation:</h2>
The magnetic field strength of a solenoid can be found by using the Ampere's law as follows;
BL = μ₀ x N x I -------------------(i)
Where;
B = magnetic field strength
L = length of the solenoid
μ₀ = magnetic constant = 1.257 x 10⁻⁶H/m
N = number of turns in the coil of the solenoid
I = current flowing through the coil of the solenoid.
<em>From the question, </em>
L = 20cm = 0.2m
N = 5000 turns
I = 10A
<em>Substitute these values into equation (i) as follows;</em>
B x 0.2 = 1.257 x 10⁻⁶ x 5000 x 10
0.2B = 6.285 x 10⁻²
<em>Solve for B;</em>
B = 6.285 x 10⁻² / 0.2
B = 31.425 x 10⁻²
B = 0.31425 T
Therefore, the magnetic field strength is 0.31425 Tesla
