Answer:
<h3>14.97m/s</h3>
Explanation:
Given
Initial velocity of the car u = 8m/s
Distance travelled by the rider S = 40m
Acceleration a = 2m/s²
Required
rider's velocity after the acceleration v
Using the equation of motion
v² = u²+2as
v² = 8²+2(2)(40)
v² = 64+160
v² = 224
v = √224
v = 14.97m/s
Hence the rider's velocity after the acceleration is 14.97m/s
One, three and five are correct.
Although if the second statement is saying that stars use gravitational force to support nuclear fusion which in turn produces energy then that would be correct, but I don’t think so :)
The interaction of electric currents or fields and magnetic fields.
I think it’s R=U/I = 120/5 = 24
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.